Expr demystified - Revision history

Diemo: more links, list formatting

2010-09-07T10:00:44Z

Diemo: links

2010-09-07T09:51:36Z

links

Diemo: list

2010-09-07T09:46:34Z

list

Adrian.g at 08:50, 7 September 2010

2010-09-07T08:50:27Z

Diemo at 09:13, 6 July 2010

2010-07-06T09:13:20Z

Diemo at 09:12, 6 July 2010

2010-07-06T09:12:55Z

Diemo at 09:09, 6 July 2010

2010-07-06T09:09:38Z

Diemo at 08:52, 6 July 2010

2010-07-06T08:52:45Z

Tremblap at 14:13, 5 July 2010

2010-07-05T14:13:48Z

Tremblap at 14:13, 5 July 2010

2010-07-05T14:13:24Z

@@ Line 1: / Line 1: @@
-This is a simple explanation for the use of the EXPR class.  See also [[Expression_Class_Arguments]] in the [[FAQ]].
+This is a simple explanation for the use of the [[expr|EXPR class]].  See also [[Expression_Class_Arguments]] in the [[FAQ]].
 == Creation - Elements of the call ==
-An EXPRession is a sentence which can be applied to the content of an [[fmat Class|fmat]] or an [[fvec Class|fvec]]. It can be created in an [[ftm.object]] (class expr) or in an FTM message box [[ftm.mess]].  In both case, it shares the same syntax:
+An EXPRession is a sentence which can be applied to the content of an [[fmat]] or an [[fvec]]. It can be created in an [[ftm.object]] (class expr) or in an FTM message box [[ftm.mess]].  In both case, it shares the same syntax:
 # it starts with expr
-# it is then followed by any code that could be entered into a ftm.mess but it needs to be surrounded by simple quotes ' '
+# it is then followed by any code that could be entered into a [[ftm.mess]] but it needs to be surrounded by simple quotes ' '
-# to be evaluated the code has to be encapsulated within parenthesis (just like any code in ftm.mess)
+# to be evaluated the code has to be encapsulated within parenthesis (just like any code in [[ftm.mess]])
 For example, the expression returning the value 1 is
@@ Line 71: / Line 71: @@
 Depending of context of use, an expr instance has access to some specific variables
-* FMAT
+* '''[[fmat]]'''
 ** Fill
 *** $row  -  the row number of currently processed element of a fmat
 *** $col  -  the col number of currently processed element of a fmat
 *** $self -  reference to currently processed fmat
+*:
-For example:
+*: For example:
+*: <pre>((new fmat 10 2) fill (new expr '(($self rows) - $row - $col)'))</pre>
- ((new fmat 10 2) fill (new expr '(($self rows) - $row - $col)'))
+*: would return a fmat filled with numbers from 10 to 1 in its first column, and 9 to 0 in the second.
+*:
 ** Apply
 *** $x    -  the value of currently processed element of fmat
 *** $self -  reference to currently processed fmat
+*:
 ** Find
 *** $x    -  the value of currently processed element of fmat
@@ Line 94: / Line 92: @@
 with $i growing row by row in a column and continuing from the beginning of the next column as if the columns were placed on after another in a single vector.
-* FVEC
+* '''[[fvec]]'''
 ** Fill
 *** $idx  -  the index number of currently processed element of a fvec
 *** $self -  reference to currently processed fvec
+*:
 ** Apply
 *** $x    -  the value of currently processed element of fvec

@@ Line 3: / Line 3: @@
 == Creation - Elements of the call ==
-An EXPRession is a sentence which can be applied to the content of an FMAT or an FVEC. It can be created in an [[ftm.object]] (class expr) or in an FTM message box [[ftm.mess]].  In both case, it shares the same syntax:
+An EXPRession is a sentence which can be applied to the content of an [[fmat Class|fmat]] or an [[fvec Class|fvec]]. It can be created in an [[ftm.object]] (class expr) or in an FTM message box [[ftm.mess]].  In both case, it shares the same syntax:
 # it starts with expr
@@ Line 25: / Line 25: @@
   expr '1, (1 + 1), (1 + 2)'
-Although all of the the comma separated parts are executed, only the last one i returned. So in the following example, after first execution the value returned would be 9:
+Although all of the the comma separated parts are executed, only the last one is returned. So in the following example, after first execution the value returned would be 9:
   expr '($var += 10), ($var - 1)'
@@ Line 104: / Line 104: @@
-[[Category:expr Class]] [[Category:Expressions]] [[Category:ftm.mess]]  [[Category:ftm.object]]
+[[Category:expr Class]] [[Category:fmat Class]] [[Category:fvec Class]]
-[[Category:FTM Documentation]]
+[[Category:Expressions]] [[Category:ftm.mess]]  [[Category:ftm.object]]
-[[Category:FAQ]]
+[[Category:FTM Documentation]] [[Category:FAQ]]

@@ Line 11: / Line 11: @@
 For example, the expression returning the value 1 is
-  expr '(1)'
+  expr '1'
 Expression returning a tuple {1 2 3} could be:
   expr '1 (1 + 1) (1 + 2)'
 But the following expression returns just 3:

@@ Line 6: / Line 6: @@
 # it starts with expr
-# it is surrounded by simple quotes ' '
+# it is then followed by any code that could be entered into a ftm.mess but it needs to be surrounded by simple quotes ' '
-# it is then encapsulated within parenthesis (to be executed like all of FTM's code)
+# to be evaluated the code has to be encapsulated within parenthesis (just like any code in ftm.mess)
 For example, the expression returning the value 1 is
   expr '(1)'
 You can use all the [[List of functions | FTM Functions]] available to create your expression. Moreover, $1, $2, etc will be replaced by values passed to your instance of expr.
@@ Line 27: / Line 41: @@
 * within [[ftm.mess]]
-when it is used as an argument to a method to another object, like in the following example:
+ (new expr '(sin $1)')
   ((new fmat 10 3) fill (new expr '(random 1 3)'))
@@ Line 33: / Line 55: @@
 == Scope of variables ==
-In the previous example, you could be tempted to use $1 and $2 to choose the boundaries of the random function within the expressionm but the variables $1 and $2 would not refer to the [[ftm.mess]] inputs, but to the expression variables.  We therefore need to pass those variables local to the [[ftm.mess]] to our newly created instance of expr by doing the following:
+In the previous example, you could be tempted to use $1 and $2 to choose the boundaries of the random function within the expression but the variables $1 and $2 would not refer to the [[ftm.mess]] inputs, but to the expression arguments. We therefore need to pass those input variables (local to the [[ftm.mess]]) as arguments to our newly created instance of expr by placing them directly after expr statement:
    ((new fmat 10 3) fill (new expr '(random $1 $2)') $1 $2)
-== Special Variables ==
+In the case our expression has been previously defined in a ftm.object and named for example '''randomize''' the above could look like this:
 Depending of context of use, an expr instance has access to some specific variables
@@ Line 43: / Line 69: @@
 * FMAT
 ** Fill
-*** $row
+*** $row  -  the row number of currently processed element of a fmat
-*** $col
+*** $col  -  the col number of currently processed element of a fmat
-*** $self
+*** $self -  reference to currently processed fmat
 ** Apply
-*** $x
+*** $x    -  the value of currently processed element of fmat
-*** $self
+*** $self -  reference to currently processed fmat
-** Lookup
+** Find
-** Find
+with $i growing row by row in a column and continuing from the beginning of the next column as if the columns were placed on after another in a single vector.
 * FVEC
 ** Fill
-*** $idx
+*** $idx  -  the index number of currently processed element of a fvec
-*** $self
+*** $self -  reference to currently processed fvec
 ** Apply
-*** $x
+*** $x    -  the value of currently processed element of fvec
-*** $self
+*** $self -  reference to currently processed fvec
 [[Category:expr Class]] [[Category:Expressions]] [[Category:ftm.mess]]  [[Category:ftm.object]]
 [[Category:FTM Documentation]]
 [[Category:FAQ]]

← Older revision		Revision as of 09:13, 6 July 2010
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−	This is a simple explanation for the use of the EXPR class. See also [[Expression_Class_Arguments]]	+	This is a simple explanation for the use of the EXPR class. See also [[Expression_Class_Arguments]] in the [[FAQ]].

	== Creation - Elements of the call ==		== Creation - Elements of the call ==

← Older revision		Revision as of 09:12, 6 July 2010
Line 1:		Line 1:
−	This is a simple ~~exaplanation~~ for the use of the EXPR class.	+	This is a simple explanation for the use of the EXPR class. See also [[Expression_Class_Arguments]]

	== Creation - Elements of the call ==		== Creation - Elements of the call ==

← Older revision		Revision as of 09:09, 6 July 2010
Line 68:		Line 68:
	** Find		** Find

−	[[Category:expr Class]] [[Category:Expressions]] [[Category:ftm.mess]] [[Category:ftm.object]] [[Category:FTM Documentation]].	+	[[Category:expr Class]] [[Category:Expressions]] [[Category:ftm.mess]] [[Category:ftm.object]]
		+	[[Category:FTM Documentation]]
		+	[[Category:FAQ]]

@@ Line 1: / Line 1: @@
-This is a simple reference for the EXPR class.
+This is a simple exaplanation for the use of the EXPR class.
 == Creation - Elements of the call ==
-An EXPRession is a sentence which can be applied to the content of an FMAT or an FVEC. It can be created in an FTM.object (class expr) or in an FTM.message.  In both case, it shares the same syntax:
+An EXPRession is a sentence which can be applied to the content of an FMAT or an FVEC. It can be created in an [[ftm.object]] (class expr) or in an FTM message box [[ftm.mess]].  In both case, it shares the same syntax:
-_ it starts with expr
+# it starts with expr
+# it is surrounded by simple quotes ' '
-_ it is surrounded by simple quotes ' '
+# it is then encapsulated within parenthesis (to be executed like all of FTM's code)
 For example, the expression returning the value 1 is
@@ Line 23: / Line 21: @@
 There are two places you can create a new expr instance:
-* within a ftm.object
+* within a [[ftm.object]]
 as shown in the ftm.class.expr.maxhelp document. On the left, you put the expression, on the right its name, the latter being the way to call the expression
-* within ftm.mess
+* within [[ftm.mess]]
 when it is used as an argument to a method to another object, like in the following example:
@@ Line 35: / Line 33: @@
 == Scope of variables ==
-In the previous example, you could be tempted to use $1 and $2 to choose the boundaries of the random function within the expressionm but the variables $1 and $2 would not refer to the ftm.mess inputs, but to the expression variables.  We therefore need to pass those variables local to the ftm.mess to our newly created instance of expr by doing the following:
+In the previous example, you could be tempted to use $1 and $2 to choose the boundaries of the random function within the expressionm but the variables $1 and $2 would not refer to the [[ftm.mess]] inputs, but to the expression variables.  We therefore need to pass those variables local to the [[ftm.mess]] to our newly created instance of expr by doing the following:
    ((new fmat 10 3) fill (new expr '(random $1 $2)') $1 $2)
@@ Line 69: / Line 67: @@
 ** Find