offload text plotting to separate library

4 files changed, 87 insertions, 25 deletions

diff --git a/Changelog b/Changelog
index 6326a38..ffc606f 100644
--- a/Changelog
+++ b/Changelog
@@ -1,3 +1,7 @@
+v2.6.2pre 
+	* Web page is in utf8 encoding
+	* Class grades histogram generation and display
+	* Weighted column show hard coded 1 as maximum possible
 v2.6.1 
 	* Users can see grading scheme
 	* Added grades in the column histogram calculation (not yet displayed)
diff --git a/GradeBook_lib.tcl b/GradeBook_lib.tcl
index b4035c3..89206b7 100755
--- a/GradeBook_lib.tcl
+++ b/GradeBook_lib.tcl
@@ -7,6 +7,7 @@ exec tclsh "$0" "$@"
 package require Tcl 8.5
 package require math::statistics
 
+source ./txtPlot.tcl
 source ./libBasicTableOperations.tcl
 
 # internal version of this code
@@ -2300,30 +2301,6 @@ proc UpdateAndCreateAsNeededInfoRow { columnname inforow val } {
 	UpdateColValue4UserNameNonWeb $columnname $inforow $val
 }
 
-proc data2txtPlot { data } {
-	set maxVal [::math::statistics::max $data ] 
-	set minVal [::math::statistics::min $data ] 
-	set diffVal [expr {$maxVal-$minVal}]
-	set chars {▁ ▂ ▃ ▄ ▅ ▆ ▇ █}; # 8 bars
-	if { $diffVal == 0 } {
-		set diffVal 1
-		set chars {▄}; # if all values are the same use mid bar
-	}
-	set barsNum [llength $chars];
-	foreach x $data {
-	  # funky 1.1 are needed to convert it to floats
-		set cnt [expr { round((1.0*$x-$minVal)/(1.1*$diffVal)*(1.1*($barsNum-1.0))) }]
-
-		# safety check on counter value
-		set cnt [expr {min($cnt, ($barsNum-1))}]
-		set cnt [expr {max($cnt, 0)}]
-
-		set bar [lrange $chars $cnt $cnt]
-		lappend strPlot $bar
-	}
-	return [join $strPlot ""]
-}
-
 proc UpdateColumnGradesHistogram { columnname } {
 	# find maximum in the column with a given name among active students
 	set hist "N/A"
diff --git a/Makefile b/Makefile
index 4238a2d..b465d5e 100644
--- a/Makefile
+++ b/Makefile
@@ -14,7 +14,7 @@ upload_location_code = physics.wm.edu:public_html/cgi-bin/
 upload_location_styles = physics.wm.edu:public_html/
 upload_location_icons = physics.wm.edu:public_html/icons/
 
-cgi_code_files = ./GradeBook.tcl ./GradeBook_lib.tcl ./libBasicTableOperations.tcl
+cgi_code_files = ./GradeBook.tcl ./GradeBook_lib.tcl ./libBasicTableOperations.tcl ./txtPlot.tcl
 files4upload_code   = $(cgi_code_files) ./gb_config.tcl
 files4upload_styles = ./GradeBook.css 
 
diff --git a/txtPlot.tcl b/txtPlot.tcl
new file mode 100644
index 0000000..8fa9c71
--- /dev/null
+++ b/txtPlot.tcl
@@ -0,0 +1,81 @@
+#!/bin/sh
+# (C) 2018 by Eugeniy Mikhailov, <evgmik@gmail.com>
+# vim:set ft=tcl: \
+exec tclsh "$0" "$@"
+
+package require math::statistics
+
+proc data2txtPlot { data } {
+	# fixme: use buil-in min and max to get rid math::statistics dependence
+	set maxVal [::math::statistics::max $data ] 
+	set minVal [::math::statistics::min $data ] 
+	set diffVal [expr {$maxVal-$minVal}]
+	set chars {▁ ▂ ▃ ▄ ▅ ▆ ▇ █}; # 8 bars
+	if { $diffVal == 0 } {
+		set diffVal 1
+		set chars {▄}; # if all values are the same use mid bar
+	}
+	set barsNum [llength $chars];
+	foreach x $data {
+	  # funky 1.1 are needed to convert it to floats
+		set cnt [expr { round((1.0*$x-$minVal)/(1.1*$diffVal)*(1.1*($barsNum-1.0))) }]
+
+		# safety check on counter value
+		set cnt [expr {min($cnt, ($barsNum-1))}]
+		set cnt [expr {max($cnt, 0)}]
+
+		set bar [lrange $chars $cnt $cnt]
+		lappend strPlot $bar
+	}
+	return [join $strPlot ""]
+}
+
+proc binInHistogram { x limits } {
+	# calculates which bin in histogram	is occupied by data with value x
+	# limits of the histogram they are used the same way as in ::math::statistics::histogram
+	set cnt 0
+	foreach lim $limits {
+		if { $x < $lim } {
+			break;
+		}
+		incr cnt
+	}
+	return $cnt;
+}
+
+proc markNthBin { i } {
+	#set mark  {█}
+	#set mark  {╽}
+	set mark  {╿}
+	#set space {▁}
+	set space {─}
+	set out {}
+	set cnt 0
+	set i [expr {max(0,$i)}]
+	while { $cnt < $i } {
+		lappend out $space
+		incr cnt
+	}
+	lappend out $mark
+	return [join $out ""]
+}
+
+# usage examples
+#
+#puts [ data2txtPlot {1 2 3 4 5 6 7 8} ]
+#puts [ data2txtPlot {1 2 3 4 5 6 7 8 7 6 5 4 3 2 1} ]
+
+#puts [ binInHistogram -10 {10 20 30}]
+#puts [ binInHistogram  15 {10 20 30}]
+#puts [ binInHistogram  25 {10 20 30}]
+#puts [ binInHistogram  35 {10 20 30}]
+#puts [ binInHistogram  30 {10 20 30}]
+#puts [ binInHistogram  10 {10 20 30}]
+
+#puts [ markNthBin 0 ]
+#puts [ markNthBin 1 ]
+#puts [ markNthBin 2 ]
+#puts [ markNthBin 10 ]
+
+
+# vim: ts=2 sw=2 foldmethod=indent: