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Posted to commits@poi.apache.org by ni...@apache.org on 2013/07/30 13:03:25 UTC
svn commit: r1508388 - in /poi/site: publish/spreadsheet/eval.html
src/documentation/content/xdocs/spreadsheet/eval.xml
Author: nick
Date: Tue Jul 30 11:03:25 2013
New Revision: 1508388
URL: http://svn.apache.org/r1508388
Log:
Add a "Why Evaluate" section to the Formula Evaluation docs
Modified:
poi/site/publish/spreadsheet/eval.html
poi/site/src/documentation/content/xdocs/spreadsheet/eval.xml
Modified: poi/site/publish/spreadsheet/eval.html
URL: http://svn.apache.org/viewvc/poi/site/publish/spreadsheet/eval.html?rev=1508388&r1=1508387&r2=1508388&view=diff
==============================================================================
--- poi/site/publish/spreadsheet/eval.html (original)
+++ poi/site/publish/spreadsheet/eval.html Tue Jul 30 11:03:25 2013
@@ -180,36 +180,55 @@ if (VERSION > 3) {
<h1>Formula Evaluation</h1>
</div>
<div class="h3">
+
+
-
-
<a name="Introduction"></a>
<div class="h3">
<h3>Introduction</h3>
</div>
-
+
<p>The POI formula evaluation code enables you to calculate the result of
- formulas in Excels sheets read-in, or created in POI. This document explains
- how to use the API to evaluate your formulas.
- </p>
-
-<div class="frame note">
-<div class="label">Note</div>
-<div class="content">.xlsx format is suported since POI 3.5, make sure yoy upgraded to that version before experimenting with this
- code. Users of all versions of POI may wish to make use of a recent
- SVN checkout, as new functions are currently being added fairly frequently.
- </div>
+ formulas in Excels sheets read-in, or created in POI. This document explains
+ how to use the API to evaluate your formulas.
+ </p>
+
+
+
+<a name="WhyEvaluate"></a>
+ <a name="Why+do+I+need+to+evaluate+formulas%3F"></a>
+<div class="h3">
+<h3>Why do I need to evaluate formulas?</h3>
</div>
-
+
+<p>The Excel file format (both .xls and .xlsx) stores a "cached" result for
+ every formula along with the formula itself. This means that when the file
+ is opened, it can be quickly displayed, without needing to spend a long
+ time calculating all of the formula results. It also means that when reading
+ a file through Apache POI, the result is quickly available to you too!
+ </p>
+
+<p>After making changes with Apache POI to either Formula Cells themselves,
+ or those that they depend on, you should normally perform a Formula
+ Evaluation to have these "cached" results updated. This is normally done
+ after all changes have been performed, but before you write the file out.
+ If you don't do this, there's a good chance that when you open the file in
+ Excel, until you go to the cell and hit enter or F9, you will either see
+ the old value or '#VALUE!' for the cell. (Sometimes Excel will notice
+ itself, and trigger a recalculation on load, but unless you know you are
+ using volatile functions it's generally best to trigger a Recalulation
+ through POI)
+ </p>
+
-
+
<a name="Status"></a>
- <a name="Status-N10024"></a>
+ <a name="Status-N10028"></a>
<div class="h3">
<h3>Status</h3>
</div>
-<p> The code currently provides implementations for all the arithmatic operators.
+<p>The code currently provides implementations for all the arithmatic operators.
It also provides implementations for approx. 140 built in
functions in Excel. The framework however makes it easy to add
implementation of new functions. See the <a href="eval-devguide.html"> Formula
@@ -290,7 +309,7 @@ switch (cellValue.getCellType()) {
<a name="EvaluateFormulaCell"></a>
- <a name="Using+FormulaEvaluator.-N1005F"></a>
+ <a name="Using+FormulaEvaluator.-N10063"></a>
<div class="h4">
<h4>Using FormulaEvaluator.evaluateFormulaCell(Cell cell)</h4>
</div>
@@ -344,7 +363,7 @@ if (cell!=null) {
<a name="EvaluateInCell"></a>
- <a name="Using+FormulaEvaluator.-N10077"></a>
+ <a name="Using+FormulaEvaluator.-N1007B"></a>
<div class="h4">
<h4>Using FormulaEvaluator.evaluateInCell(Cell cell)</h4>
</div>
@@ -576,7 +595,6 @@ for(int sheetNum = 0; sheetNum < wb.g
-<div id="authors" align="right">by Amol Deshmukh</div>
</div>
</div>
</div>
Modified: poi/site/src/documentation/content/xdocs/spreadsheet/eval.xml
URL: http://svn.apache.org/viewvc/poi/site/src/documentation/content/xdocs/spreadsheet/eval.xml?rev=1508388&r1=1508387&r2=1508388&view=diff
==============================================================================
--- poi/site/src/documentation/content/xdocs/spreadsheet/eval.xml (original)
+++ poi/site/src/documentation/content/xdocs/spreadsheet/eval.xml Tue Jul 30 11:03:25 2013
@@ -20,27 +20,41 @@
<!DOCTYPE document PUBLIC "-//APACHE//DTD Documentation V1.1//EN" "../dtd/document-v11.dtd">
<document>
- <header>
- <title>Formula Evaluation</title>
- <authors>
- <person email="amoweb@yahoo.com" name="Amol Deshmukh" id="AD"/>
- </authors>
- </header>
- <body>
- <section><title>Introduction</title>
- <p>The POI formula evaluation code enables you to calculate the result of
- formulas in Excels sheets read-in, or created in POI. This document explains
- how to use the API to evaluate your formulas.
- </p>
- <note>.xlsx format is suported since POI 3.5, make sure yoy upgraded to that version before experimenting with this
- code. Users of all versions of POI may wish to make use of a recent
- SVN checkout, as new functions are currently being added fairly frequently.
- </note>
- </section>
+ <header>
+ <title>Formula Evaluation</title>
+ </header>
+ <body>
+ <section><title>Introduction</title>
+ <p>The POI formula evaluation code enables you to calculate the result of
+ formulas in Excels sheets read-in, or created in POI. This document explains
+ how to use the API to evaluate your formulas.
+ </p>
+ </section>
+
+ <anchor id="WhyEvaluate"/>
+ <section><title>Why do I need to evaluate formulas?</title>
+ <p>The Excel file format (both .xls and .xlsx) stores a "cached" result for
+ every formula along with the formula itself. This means that when the file
+ is opened, it can be quickly displayed, without needing to spend a long
+ time calculating all of the formula results. It also means that when reading
+ a file through Apache POI, the result is quickly available to you too!
+ </p>
+ <p>After making changes with Apache POI to either Formula Cells themselves,
+ or those that they depend on, you should normally perform a Formula
+ Evaluation to have these "cached" results updated. This is normally done
+ after all changes have been performed, but before you write the file out.
+ If you don't do this, there's a good chance that when you open the file in
+ Excel, until you go to the cell and hit enter or F9, you will either see
+ the old value or '#VALUE!' for the cell. (Sometimes Excel will notice
+ itself, and trigger a recalculation on load, but unless you know you are
+ using volatile functions it's generally best to trigger a Recalulation
+ through POI)
+ </p>
+ </section>
- <anchor id="Status"/>
- <section><title>Status</title>
- <p> The code currently provides implementations for all the arithmatic operators.
+ <anchor id="Status"/>
+ <section><title>Status</title>
+ <p>The code currently provides implementations for all the arithmatic operators.
It also provides implementations for approx. 140 built in
functions in Excel. The framework however makes it easy to add
implementation of new functions. See the <link href="eval-devguide.html"> Formula
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