Improvements to formula evaluation treatment of -0.0. (Refinements to fix for bug 47198
git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@797258 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
Josh Micich
parent
e6d41ed590
commit
32d0c7213e
@ -34,14 +34,17 @@ public final class PercentEval implements OperationEval {
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if (args.length != 1) {
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return ErrorEval.VALUE_INVALID;
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}
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double d0;
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double d;
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try {
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ValueEval ve = OperandResolver.getSingleValue(args[0], srcRow, srcCol);
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d0 = OperandResolver.coerceValueToDouble(ve);
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d = OperandResolver.coerceValueToDouble(ve);
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} catch (EvaluationException e) {
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return e.getErrorEval();
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}
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return new NumberEval(d0 / 100);
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if (d == 0.0) { // this '==' matches +0.0 and -0.0
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return NumberEval.ZERO;
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}
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return new NumberEval(d / 100);
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}
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public int getNumberOfOperands() {
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@ -19,7 +19,7 @@ package org.apache.poi.hssf.record.formula.eval;
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/**
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* Base class for all comparison operator evaluators
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*
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*
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* @author Amol S. Deshmukh < amolweb at ya hoo dot com >
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*/
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public abstract class RelationalOperationEval implements OperationEval {
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@ -108,10 +108,7 @@ public abstract class RelationalOperationEval implements OperationEval {
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if (vb instanceof NumberEval) {
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NumberEval nA = (NumberEval) va;
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NumberEval nB = (NumberEval) vb;
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if (nA.getNumberValue() == nB.getNumberValue()) {
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// Excel considers -0.0 == 0.0 which is different to Double.compare()
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return 0;
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}
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// Excel considers -0.0 < 0.0 which is the same as Double.compare()
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return Double.compare(nA.getNumberValue(), nB.getNumberValue());
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}
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}
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@ -26,13 +26,19 @@ abstract class TwoOperandNumericOperation implements OperationEval {
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ValueEval ve = OperandResolver.getSingleValue(arg, srcCellRow, srcCellCol);
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return OperandResolver.coerceValueToDouble(ve);
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}
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public final Eval evaluate(Eval[] args, int srcCellRow, short srcCellCol) {
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double result;
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try {
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double d0 = singleOperandEvaluate(args[0], srcCellRow, srcCellCol);
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double d1 = singleOperandEvaluate(args[1], srcCellRow, srcCellCol);
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result = evaluate(d0, d1);
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if (result == 0.0) { // this '==' matches +0.0 and -0.0
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// Excel converts -0.0 to +0.0 for '*', '/', '%', '+' and '^'
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if (!(this instanceof SubtractEval)) {
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return NumberEval.ZERO;
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}
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}
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if (Double.isNaN(result) || Double.isInfinite(result)) {
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return ErrorEval.NUM_ERROR;
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}
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@ -20,7 +20,7 @@ package org.apache.poi.hssf.record.formula.eval;
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/**
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* @author Amol S. Deshmukh < amolweb at ya hoo dot com >
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*
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*
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*/
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public final class UnaryMinusEval implements OperationEval {
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@ -41,6 +41,9 @@ public final class UnaryMinusEval implements OperationEval {
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} catch (EvaluationException e) {
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return e.getErrorEval();
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}
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if (d == 0.0) { // this '==' matches +0.0 and -0.0
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return NumberEval.ZERO;
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}
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return new NumberEval(-d);
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}
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@ -26,16 +26,16 @@ import java.math.BigInteger;
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* <ul>
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* <li>No more than 15 significant figures are output (java does 18).</li>
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* <li>The sign char for the exponent is included even if positive</li>
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* <li>Special values (<tt>NaN</tt> and <tt>Infinity</tt>) get rendered like the ordinary
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* <li>Special values (<tt>NaN</tt> and <tt>Infinity</tt>) get rendered like the ordinary
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* number that the bit pattern represents.</li>
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* <li>Denormalised values (between ±2<sup>-1074</sup> and ±2<sup>-1022</sup>
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* are displayed as "0"</sup>
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* </ul>
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* IEEE 64-bit Double Rendering Comparison
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*
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*
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* <table border="1" cellpadding="2" cellspacing="0" summary="IEEE 64-bit Double Rendering Comparison">
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* <tr><th>Raw bits</th><th>Java</th><th>Excel</th></tr>
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*
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*
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* <tr><td>0x0000000000000000L</td><td>0.0</td><td>0</td></tr>
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* <tr><td>0x3FF0000000000000L</td><td>1.0</td><td>1</td></tr>
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* <tr><td>0x3FF00068DB8BAC71L</td><td>1.0001</td><td>1.0001</td></tr>
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@ -96,8 +96,8 @@ import java.math.BigInteger;
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* <tr><td>0x7FFFFFFFFFFFFFFFL</td><td>NaN</td><td>3.5953862697246E+308</td></tr>
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* <tr><td>0xFFF7FFFFFFFFFFFFL</td><td>NaN</td><td>2.6965397022935E+308</td></tr>
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* </table>
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*
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* <b>Note</b>:
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*
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* <b>Note</b>:
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* Excel has inconsistent rules for the following numeric operations:
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* <ul>
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* <li>Conversion to string (as handled here)</li>
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@ -105,10 +105,10 @@ import java.math.BigInteger;
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* <li>Conversion from text</li>
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* <li>General arithmetic</li>
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* </ul>
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* Excel's text to number conversion is not a true <i>inverse</i> of this operation. The
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* Excel's text to number conversion is not a true <i>inverse</i> of this operation. The
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* allowable ranges are different. Some numbers that don't correctly convert to text actually
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* <b>do</b> get handled properly when used in arithmetic evaluations.
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*
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*
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* @author Josh Micich
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*/
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public final class NumberToTextConverter {
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@ -119,49 +119,49 @@ public final class NumberToTextConverter {
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private static final int FRAC_BITS_WIDTH = EXPONENT_SHIFT;
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private static final int EXPONENT_BIAS = 1023;
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private static final long FRAC_ASSUMED_HIGH_BIT = ( 1L<<EXPONENT_SHIFT );
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private static final long EXCEL_NAN_BITS = 0xFFFF0420003C0000L;
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private static final int MAX_TEXT_LEN = 20;
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private static final int DEFAULT_COUNT_SIGNIFICANT_DIGITS = 15;
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private static final int MAX_EXTRA_ZEROS = MAX_TEXT_LEN - DEFAULT_COUNT_SIGNIFICANT_DIGITS;
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private static final float LOG2_10 = 3.32F;
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private NumberToTextConverter() {
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// no instances of this class
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}
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/**
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* Converts the supplied <tt>value</tt> to the text representation that Excel would give if
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* Converts the supplied <tt>value</tt> to the text representation that Excel would give if
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* the value were to appear in an unformatted cell, or as a literal number in a formula.<br/>
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* Note - the results from this method differ slightly from those of <tt>Double.toString()</tt>
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* In some special cases Excel behaves quite differently. This function attempts to reproduce
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* those results.
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* those results.
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*/
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public static String toText(double value) {
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return rawDoubleBitsToText(Double.doubleToLongBits(value));
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}
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/* package */ static String rawDoubleBitsToText(long pRawBits) {
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long rawBits = pRawBits;
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boolean isNegative = rawBits < 0; // sign bit is in the same place for long and double
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if (isNegative) {
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rawBits &= 0x7FFFFFFFFFFFFFFFL;
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}
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int biasedExponent = (int) ((rawBits & expMask) >> EXPONENT_SHIFT);
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if (biasedExponent == 0) {
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// value is 'denormalised' which means it is less than 2^-1022
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// excel displays all these numbers as zero, even though calculations work OK
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return "0";
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return isNegative ? "-0" : "0";
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}
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int exponent = biasedExponent - EXPONENT_BIAS;
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int exponent = biasedExponent - EXPONENT_BIAS;
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long fracBits = FRAC_ASSUMED_HIGH_BIT | rawBits & FRAC_MASK;
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// Start by converting double value to BigDecimal
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BigDecimal bd;
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if (biasedExponent == 0x07FF) {
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@ -175,26 +175,26 @@ public final class NumberToTextConverter {
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isNegative = false; // except that the sign bit is ignored
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}
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bd = convertToBigDecimal(exponent, fracBits);
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return formatBigInteger(isNegative, bd.unscaledValue(), bd.scale());
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}
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private static BigDecimal convertToBigDecimal(int exponent, long fracBits) {
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byte[] joob = {
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(byte) (fracBits >> 48),
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(byte) (fracBits >> 40),
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(byte) (fracBits >> 32),
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(byte) (fracBits >> 24),
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(byte) (fracBits >> 16),
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(byte) (fracBits >> 8),
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(byte) (fracBits >> 0),
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(byte) (fracBits >> 48),
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(byte) (fracBits >> 40),
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(byte) (fracBits >> 32),
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(byte) (fracBits >> 24),
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(byte) (fracBits >> 16),
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(byte) (fracBits >> 8),
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(byte) (fracBits >> 0),
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};
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BigInteger bigInt = new BigInteger(joob);
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int lastSigBitIndex = exponent-FRAC_BITS_WIDTH;
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if(lastSigBitIndex < 0) {
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BigInteger shifto = new BigInteger("1").shiftLeft(-lastSigBitIndex);
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int scale = 1 -(int) (lastSigBitIndex/LOG2_10);
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int scale = 1 -(int) (lastSigBitIndex/LOG2_10);
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BigDecimal bd1 = new BigDecimal(bigInt);
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BigDecimal bdShifto = new BigDecimal(shifto);
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return bd1.divide(bdShifto, scale, BigDecimal.ROUND_HALF_UP);
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@ -208,10 +208,10 @@ public final class NumberToTextConverter {
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if (scale < 0) {
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throw new RuntimeException("negative scale");
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}
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StringBuffer sb = new StringBuffer(unscaledValue.toString());
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int numberOfLeadingZeros = -1;
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int unscaledLength = sb.length();
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if (scale > 0 && scale >= unscaledLength) {
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// less than one
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@ -226,7 +226,7 @@ public final class NumberToTextConverter {
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}
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return sb.toString();
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}
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private static int getNumberOfSignificantFiguresDisplayed(int exponent) {
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int nLostDigits; // number of significand digits lost due big exponents
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if(exponent > 99) {
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@ -241,19 +241,19 @@ public final class NumberToTextConverter {
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}
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return DEFAULT_COUNT_SIGNIFICANT_DIGITS - nLostDigits;
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}
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private static boolean needsScientificNotation(int nDigits) {
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return nDigits > MAX_TEXT_LEN;
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}
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private static void formatGreaterThanOne(StringBuffer sb, int nIntegerDigits) {
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int maxSigFigs = getNumberOfSignificantFiguresDisplayed(nIntegerDigits);
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int decimalPointIndex = nIntegerDigits;
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boolean roundCausedCarry = performRound(sb, 0, maxSigFigs);
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int endIx = Math.min(maxSigFigs, sb.length()-1);
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int nSigFigures;
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if(roundCausedCarry) {
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sb.insert(0, '1');
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@ -292,11 +292,11 @@ public final class NumberToTextConverter {
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if (pAbsExponent < 1) {
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throw new IllegalArgumentException("abs(exponent) must be positive");
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}
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int numberOfLeadingZeros = pAbsExponent-1;
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int absExponent = pAbsExponent;
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int maxSigFigs = getNumberOfSignificantFiguresDisplayed(-absExponent);
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int absExponent = pAbsExponent;
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int maxSigFigs = getNumberOfSignificantFiguresDisplayed(-absExponent);
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boolean roundCausedCarry = performRound(sb, 0, maxSigFigs);
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int nRemainingSigFigs;
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if(roundCausedCarry) {
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@ -309,9 +309,9 @@ public final class NumberToTextConverter {
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nRemainingSigFigs = countSignifantDigits(sb, 0 + maxSigFigs);
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sb.setLength(nRemainingSigFigs);
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}
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int normalLength = 2 + numberOfLeadingZeros + nRemainingSigFigs; // 2 == "0.".length()
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if (needsScientificNotation(normalLength)) {
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if (sb.length()>1) {
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sb.insert(1, '.');
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@ -319,7 +319,7 @@ public final class NumberToTextConverter {
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sb.append('E');
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sb.append('-');
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appendExp(sb, absExponent);
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} else {
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} else {
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sb.insert(0, "0.");
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for(int i=numberOfLeadingZeros; i>0; i--) {
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sb.insert(2, '0');
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@ -345,7 +345,7 @@ public final class NumberToTextConverter {
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return;
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}
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sb.append(val);
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}
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@ -391,12 +391,12 @@ public final class NumberToTextConverter {
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while(sb.charAt(changeDigitIx) == '9') {
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sb.setCharAt(changeDigitIx, '0');
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changeDigitIx--;
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// All nines, rounded up. Notify caller
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// All nines, rounded up. Notify caller
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if(changeDigitIx < 0) {
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return true;
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}
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}
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// no more '9's to round up.
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// no more '9's to round up.
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// Last digit to be changed is still inside sb
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char prevDigit = sb.charAt(changeDigitIx);
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sb.setCharAt(changeDigitIx, (char) (prevDigit + 1));
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@ -22,11 +22,11 @@ import junit.framework.TestSuite;
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/**
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* Collects all tests the package <tt>org.apache.poi.hssf.record.formula.eval</tt>.
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*
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*
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* @author Josh Micich
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*/
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public class AllFormulaEvalTests {
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public static Test suite() {
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TestSuite result = new TestSuite(AllFormulaEvalTests.class.getName());
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result.addTestSuite(TestAreaEval.class);
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@ -36,6 +36,7 @@ public class AllFormulaEvalTests {
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result.addTestSuite(TestExternalFunction.class);
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result.addTestSuite(TestFormulaBugs.class);
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result.addTestSuite(TestFormulasFromSpreadsheet.class);
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result.addTestSuite(TestMinusZeroResult.class);
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result.addTestSuite(TestMissingArgEval.class);
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result.addTestSuite(TestPercentEval.class);
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result.addTestSuite(TestRangeEval.class);
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@ -93,12 +93,21 @@ public final class TestEqualEval extends TestCase {
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}
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/**
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* Excel considers -0.0 to be equal to 0.0
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* Bug 47198 involved a formula "-A1=0" where cell A1 was 0.0.
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* Excel evaluates "-A1=0" to TRUE, not because it thinks -0.0==0.0
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* but because "-A1" evaluated to +0.0
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* <p/>
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* Note - the original diagnosis of bug 47198 was that
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* "Excel considers -0.0 to be equal to 0.0" which is NQR
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* See {@link TestMinusZeroResult} for more specific tests regarding -0.0.
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*/
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public void testZeroEquality_bug47198() {
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NumberEval zero = new NumberEval(0.0);
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NumberEval mZero = (NumberEval) UnaryMinusEval.instance.evaluate(new Eval[] { zero, }, 0,
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(short) 0);
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if (Double.doubleToLongBits(mZero.getNumberValue()) == 0x8000000000000000L) {
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throw new AssertionFailedError("Identified bug 47198: unary minus should convert -0.0 to 0.0");
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}
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Eval[] args = { zero, mZero, };
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BoolEval result = (BoolEval) EqualEval.instance.evaluate(args, 0, (short) 0);
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if (!result.getBooleanValue()) {
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@ -0,0 +1,148 @@
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/* ====================================================================
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Licensed to the Apache Software Foundation (ASF) under one or more
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contributor license agreements. See the NOTICE file distributed with
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this work for additional information regarding copyright ownership.
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The ASF licenses this file to You under the Apache License, Version 2.0
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(the "License"); you may not use this file except in compliance with
|
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the License. You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
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See the License for the specific language governing permissions and
|
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limitations under the License.
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==================================================================== */
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package org.apache.poi.hssf.record.formula.eval;
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import junit.framework.ComparisonFailure;
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import junit.framework.TestCase;
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import org.apache.poi.util.HexDump;
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/**
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* IEEE 754 defines a quantity '-0.0' which is distinct from '0.0'.
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* Negative zero is not easy to observe in Excel, since it is usually converted to 0.0.
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* (Note - the results of XLL add-in functions don't seem to be converted, so they are one
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* reliable avenue to observe Excel's treatment of '-0.0' as an operand.)
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* <p/>
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* POI attempts to emulate Excel faithfully, so this class tests
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* two aspects of '-0.0' in formula evaluation:
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* <ol>
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* <li>For most operation results '-0.0' is converted to '0.0'.</li>
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* <li>Comparison operators have slightly different rules regarding '-0.0'.</li>
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* </ol>
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* @author Josh Micich
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*/
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public final class TestMinusZeroResult extends TestCase {
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private static final double MINUS_ZERO = -0.0;
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public void testSimpleOperators() {
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// unary plus is a no-op
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checkEval(MINUS_ZERO, UnaryPlusEval.instance, MINUS_ZERO);
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// most simple operators convert -0.0 to +0.0
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checkEval(0.0, UnaryMinusEval.instance, 0.0);
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checkEval(0.0, PercentEval.instance, MINUS_ZERO);
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checkEval(0.0, MultiplyEval.instance, MINUS_ZERO, 1.0);
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checkEval(0.0, DivideEval.instance, MINUS_ZERO, 1.0);
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checkEval(0.0, PowerEval.instance, MINUS_ZERO, 1.0);
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// but SubtractEval does not convert -0.0, so '-' and '+' work like java
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checkEval(MINUS_ZERO, SubtractEval.instance, MINUS_ZERO, 0.0); // this is the main point of bug 47198
|
||||
checkEval(0.0, AddEval.instance, MINUS_ZERO, 0.0);
|
||||
}
|
||||
|
||||
/**
|
||||
* These results are hard to see in Excel (since -0.0 is usually converted to +0.0 before it
|
||||
* gets to the comparison operator)
|
||||
*/
|
||||
public void testComparisonOperators() {
|
||||
checkEval(false, EqualEval.instance, 0.0, MINUS_ZERO);
|
||||
checkEval(true, GreaterThanEval.instance, 0.0, MINUS_ZERO);
|
||||
checkEval(true, LessThanEval.instance, MINUS_ZERO, 0.0);
|
||||
}
|
||||
|
||||
public void testTextRendering() {
|
||||
confirmTextRendering("-0", MINUS_ZERO);
|
||||
// sub-normal negative numbers also display as '-0'
|
||||
confirmTextRendering("-0", Double.longBitsToDouble(0x8000100020003000L));
|
||||
}
|
||||
|
||||
/**
|
||||
* Uses {@link ConcatEval} to force number-to-text conversion
|
||||
*/
|
||||
private static void confirmTextRendering(String expRendering, double d) {
|
||||
Eval[] args = { StringEval.EMPTY_INSTANCE, new NumberEval(d), };
|
||||
StringEval se = (StringEval) ConcatEval.instance.evaluate(args, -1, (short)-1);
|
||||
String result = se.getStringValue();
|
||||
assertEquals(expRendering, result);
|
||||
}
|
||||
|
||||
private static void checkEval(double expectedResult, OperationEval instance, double... dArgs) {
|
||||
NumberEval result = (NumberEval) evaluate(instance, dArgs);
|
||||
assertDouble(expectedResult, result.getNumberValue());
|
||||
}
|
||||
private static void checkEval(boolean expectedResult, OperationEval instance, double... dArgs) {
|
||||
BoolEval result = (BoolEval) evaluate(instance, dArgs);
|
||||
assertEquals(expectedResult, result.getBooleanValue());
|
||||
}
|
||||
private static Eval evaluate(OperationEval instance, double... dArgs) {
|
||||
Eval[] evalArgs;
|
||||
evalArgs = new Eval[dArgs.length];
|
||||
for (int i = 0; i < evalArgs.length; i++) {
|
||||
evalArgs[i] = new NumberEval(dArgs[i]);
|
||||
}
|
||||
Eval r = instance.evaluate(evalArgs, -1, (short)-1);
|
||||
return r;
|
||||
}
|
||||
|
||||
/**
|
||||
* Not really a POI test - just shows similar behaviour of '-0.0' in Java.
|
||||
*/
|
||||
public void testJava() {
|
||||
|
||||
assertEquals(0x8000000000000000L, Double.doubleToLongBits(MINUS_ZERO));
|
||||
|
||||
// The simple operators consider all zeros to be the same
|
||||
assertTrue(MINUS_ZERO == MINUS_ZERO);
|
||||
assertTrue(MINUS_ZERO == +0.0);
|
||||
assertFalse(MINUS_ZERO < +0.0);
|
||||
|
||||
// Double.compare() considers them different
|
||||
assertTrue(Double.compare(MINUS_ZERO, +0.0) < 0);
|
||||
|
||||
// multiplying zero by any negative quantity yields minus zero
|
||||
assertDouble(MINUS_ZERO, 0.0*-1);
|
||||
assertDouble(MINUS_ZERO, 0.0*-1e300);
|
||||
assertDouble(MINUS_ZERO, 0.0*-1e-300);
|
||||
|
||||
// minus zero can be produced as a result of underflow
|
||||
assertDouble(MINUS_ZERO, -1e-300 / 1e100);
|
||||
|
||||
// multiplying or dividing minus zero by a positive quantity yields minus zero
|
||||
assertDouble(MINUS_ZERO, MINUS_ZERO * 1.0);
|
||||
assertDouble(MINUS_ZERO, MINUS_ZERO / 1.0);
|
||||
|
||||
// subtracting positive zero gives minus zero
|
||||
assertDouble(MINUS_ZERO, MINUS_ZERO - 0.0);
|
||||
// BUT adding positive zero gives positive zero
|
||||
assertDouble(0.0, MINUS_ZERO + 0.0); // <<----
|
||||
}
|
||||
|
||||
/**
|
||||
* Just so there is no ambiguity. The two double values have to be exactly equal
|
||||
*/
|
||||
private static void assertDouble(double a, double b) {
|
||||
long bitsA = Double.doubleToLongBits(a);
|
||||
long bitsB = Double.doubleToLongBits(b);
|
||||
if (bitsA != bitsB) {
|
||||
throw new ComparisonFailure("value different to expected",
|
||||
new String(HexDump.longToHex(bitsA)), new String(HexDump.longToHex(bitsB)));
|
||||
}
|
||||
}
|
||||
}
|
||||
Loading…
Reference in New Issue
Block a user