SUBSTITUTE CHARACTER

SUBSTITUTE CHARACTER

Support Command

Specify the character to use as the substitution character.

The substitute character signifies that the parameter following it should be replaced with the value of that parameter.

The following name types can be substituted.

1. If the name is a parameter, the value of the parameter will be substituted.

2. If the name is a string, the value of the string will be substituted.

3. If the name is a variable, Dataplot will check to see if an alias for the variable name has been defined (via the VARIABLE LABEL command). If so, that alias will be substituted. If an alias has not been defined, the substitution may be unpredictable.

   If Y is a variable, the following is not currently supported

   LET STRING S = ^Y(2)

   For this case, you need to do something like

   LET A = Y(2)
   LET STRING S = ^A
   

4. If you have defined row labels (via READ ROW LABEL or LET ... = ROW LABEL ...), you can do something like
   ^ROWLABEL^K

   where K in an index to the desired row of the row labels.

5. Any other name type will result in an error message with no substitution being performed.

SUBSTITUTE CHARACTER <char>
where <char> is the character to use as the substitute character.

SUBSTITUTE CHARACTER @
SUBSTITUTE CHARACTER ^

Generally it is not necessary to change the substitute character. The one exception is if you want to define strings that contain the default substitute character.

The substitute character can be used effectively with the LOOP command. For example, assume that variables Y1 thru YN and strings S1 and SN have been previously defined:

 
LOOP FOR K = 1 1 N
    TITLE Y^K VS X
    LEGEND 1 ^S^K
    PLOT Y^K VS X
END OF LOOP
    

Note the distinction between Y^K in the PLOT command and ^S^K in the LEGEND command. For the plot command, we want PLOT Y1 VS X while for the LEGEND command we want to insert the value of the string S1. This is the reason that the Y^K has no preceding ^ while the ^S^K does.

The following characters are used to determine the end of the parameter name:

	-	a space
(	-	a left parenthesis
)	-	a right parenthesis
"	-	a quote character
&	-	an ampersand character
.	-	a period
^	-	another substitute character
,	-	a comma
:	-	a colon
;	-	a semi-colon
]	-	a right bracket
+	-	a plus
-	-	a minus
*	-	an asterisk
/	-	a forward slash

The substitution is performed before the command is interpreted.

If the parameter is undefined, it is replaced with a space character in the command line.

The VALU() command also performs parameter substitution. However, it only works for a few commands (specifically LEGEND, TITLE, LABEL, and TEXT) while the substitute character works on any command.

The substitute character can also be changed with the command
SET REPLACE <char>

There may be occassions where you want to suppress the character substitution. For examle, you may want to use the "^" character in a string. You can suspend character substitution with the command
SET COMMAND SUBSTITUTION OFF

To resume character substitution, enter

SET COMMAND SUBSTITUTION ON

If you are substituting for a parameter, there are several ways you can control the appearance.
1. You can use the ROUND command. For example,
   LET CC = ROUND(CC,2)
   LET STRING S = CORR: ^CC
   

2. By default, parameters are expanded into numeric format (e.g., 0.0017). If you would like the parameter expanded in exponential format, enter the command
   SET PARAMETER EXPANSION EXPONENTIAL

   To restore the default, enter

   SET PARAMETER EXPANSION NUMERIC

3. For the most control, you can specify a Fortran format by entering the command
   SET SUBSTITUTION FORMAT <string>

   For example,

   SET SUBSTITUTION FORMAT F4.2
   SET SUBSTITUTION FORMAT E15.7
   

   To turn this off, enter

   SET SUBSTITUTION FORMAT OFF

   Dataplot uses the specified format with an internal Fortran WRITE statement. That is

   WRITE(ISTR,IFORMT,ERR=statement)VAL

   where IFORMT is the specified format and VAL is the value of the parameter. Dataplot does no parsing or error checking on the specified format. Typically, only F, E, or G formats should be used. If there is an error using the Fortran format specification, Dataplot will revert to its default parameter expansion (no error message will be generated). The format string is limited to a maximum of 8 characters and the maximum number of characters for the expanded parameter is 20.

The default substitute character is ^ .

REPLACEMENT CHARACTER

LOOP	=	Perform a loop.
VALU()	=	Perform parameter substitution within certain commands.
TERMINATOR CHARACTER	=	Define the character that terminates a command.
CONTINUE CHARACTER	=	Define the character that specifies that a command is continued onto the next line.

XX

Pre-1987
2000/01: Support for VARIABLE LABEL substitution
2007/09: Support for ^ROWLABEL^K
2019/01: Support for SET SUBSTITUTION FORMAT
2019/01: Support for SET COMMAND SUBSTITUTION

 
. Step 1:   Read the data
.
skip 25
read weibbury.dat y
skip 0
.
. Step 2:   Maximum likelihood estimates
.
set write decimals 5
weibull mle y
let gamma = gammaml
let pploc   = 0
let ppscale = alphaml
.
title case asis
label case asis
title Weibull Probability Plot
y1label Sorted Data
x1label Percentiles for Fitted Weibull Distribution
character circle
character hw 1 0.75
character fill on
line blank
.
. Step 3:   Generate probability plot
.
weibull probability plot y
.
let gamma = round(gamma,2)
move 20 85
text Gamma = ^gamma
let ppscale = round(ppscale,2)
move 20 82
text Scale = ^ppscale
let ppcc = round(ppcc,3)
move 20 79
text PPCC = ^ppcc