Difference between revisions of "Working With String Data in Recital"

Revision as of 15:33, 21 July 2010

Working With String Data in Recital

Changing the Case of a String

• lower() - convert a string to lower case

character = lower(string as character)

• upper() - convert a string to upper case

character = upper(string as character)

• proper() - convert a string to lower case with the first character to upper case

character = proper(string as character)

Converting to and from ASCII Values

• asc() - return the numeric ASCII value of a character.

numeric = asc(string as character)

• chr() - return the character corresponding to a numeric ASCII value.

character = chr(ASCII as numeric)

Printing Formatted Strings in Recital

Recital provides three functions for the output of strings with 'C' style parameter replacement and formatting.

The printf() function outputs the string to the current output: screen, printer destination, alternate file, etc..

printf(format as character, args [,...])

The sprintf() function returns the formatted string as a character value.

character=sprintf(format as character, args [,...])

The fprintf() function writes the formatted string to an open file using a file pointer reference.

fprintf(file pointer as numeric, format as character, args [,...])

Recital printf Formatting Specifiers

Formatting sequences can also contain the following options. These are specified in order, between the '%' and the data type letter.

Example code printf()

// When %s is specified, the corresponding argument is converted to 
// character format (similar to specifying etos()).
// Widths correspond to the default values, e.g. numerics are 10
printf('It is %s, %s to be more precise\n',year(date()),datetime())
printf('The value of pi is %s\n',pi())
printf('They cost %s per %s\n',$99,100)
printf('Logicals can be %s or %s\n',.T.,.F.)
// Formatting sequences can contain a width, which will left pad with spaces 
printf('Right-justify and pad left: %10s this\n','Like')
// Left justify by placing a '-' directly following the '%' character 
printf('Left-justify and pad right: %-10s this\n','Like')
// %d is for numerics
printf('It is %d\n',year(date()))
// %t and %T are for formating datetime data types.
printf('It is %d, %t to be more precise\n',year(date()),datetime())
printf('It is %d, %T to be even more precise\n',year(date()),datetime())
// %f is for floating point numerics
printf('The value of pi is %f\n',pi())
// Decimal places can also be specified for floating point numerics (%f) 
printf('The value of pi to two decimal places is %4.2f\n',pi())
// %y is for formatting currency data types
printf('They cost %y per %d\n',$99,100)
printf('They cost %y per %d\n',$99,1000)
printf('They cost %y per %d\n',$99,10000)
//%l and %L are for formatting logical datatypes.
printf('Logicals can be %l or %l\n',.T.,.F.)
printf('Logicals can also be %L or %L\n',.T.,.F.)

Example code sprintf()

// When %s is specified, the corresponding argument is converted to 
// character format (similar to specifying etos()).
// Widths correspond to the default values, e.g. numerics are 10
cVAR=sprintf('It is %s, %s to be more precise',year(date()),datetime())
echo cVAR
cVAR=sprintf('The value of pi is %s',pi())
echo cVAR
cVAR=sprintf('They cost %s per %s',$99,100)
echo cVAR
cVAR=sprintf('Logicals can be %s or %s',.T.,.F.)
echo cVAR
// Formatting characters can contain a width, which will left pad with spaces 
cVAR=sprintf('Right-justify and pad left: %10s this','Like')
echo cVAR
// Left justify by placing a '-' directly following the '%' character 
cVAR=sprintf('Left-justify and pad right: %-10s this','Like')
echo cVAR
// %d is for numerics
cVAR=sprintf('It is %d',year(date()))
echo cVAR
// %t and %T are for formating datetime data types.
cVAR=sprintf('It is %d, %t to be more precise',year(date()),datetime())
echo cVAR
cVAR=sprintf('It is %d, %T to be even more precise',year(date()),datetime())
echo cVAR
// %f is for floating point numerics
cVAR=sprintf('The value of pi is %f',pi())
echo cVAR
// Decimal places can also be specified for floating point numerics (%f)
cVAR=sprintf('The value of pi to two decimal places is %4.2f',pi())
echo cVAR
// %y is for formatting currency data types
cVAR=sprintf('They cost %y per %d',$99,100)
echo cVAR
cVAR=sprintf('They cost %y per %d',$99,1000)
echo cVAR
cVAR=sprintf('They cost %y per %d',$99,10000)
echo cVAR
//%l and %L are for formatting logical datatypes.
cVAR=sprintf('Logicals can be %l or %l',.T.,.F.)
echo cVAR
cVAR=sprintf('Logicals can also be %L or %L',.T.,.F.)
echo cVAR

Example code fprintf()

fp=fcreate('fprintf.txt')
// When %s is specified, the corresponding argument is converted to 
// character format (similar to specifying etos()).
// Widths correspond to the default values, e.g. numerics are 10
fprintf(fp,'It is %s, %s to be more precise\n',year(date()),datetime())
fprintf(fp,'The value of pi is %s\n',pi())
fprintf(fp,'They cost %s per %s\n',$99,100)
fprintf(fp,'Logicals can be %s or %s\n',.T.,.F.)
// Formatting characters can contain a width, which will left pad with spaces 
fprintf(fp,'Right-justify and pad left: %10s this\n','Like')
// Left justify by placing a '-' directly following the '%' character 
fprintf(fp,'Left-justify and pad right: %-10s this\n','Like')
// %d is for numerics
fprintf(fp,'It is %d\n',year(date()))
// %t and %T are for formating datetime data types.
fprintf(fp,'It is %d, %t to be more precise\n',year(date()),datetime())
fprintf(fp,'It is %d, %T to be even more precise\n',year(date()),datetime())
// %f is for floating point numerics
fprintf(fp,'The value of pi is %f\n',pi())
// Decimal places can also be specified for floating point numerics (%f)
fprintf(fp,'The value of pi to two decimal places is %4.2f\n',pi())
// %y is for formatting currency data types
fprintf(fp,'They cost %y per %d\n',$99,100)
fprintf(fp,'They cost %y per %d\n',$99,1000)
fprintf(fp,'They cost %y per %d\n',$99,10000)
//%l and %L are for formatting logical datatypes.
fprintf(fp,'Logicals can be %l or %l\n',.T.,.F.)
fprintf(fp,'Logicals can also be %L or %L\n',.T.,.F.)
fclose(fp)

Output

It is       2009, 11/11/2009 11:41:51 AM to be more precise
The value of pi is  3.1415926
They cost $99.0000 per        100
Logicals can be True or False
Right-justify and pad left:       Like this
Left-justify and pad right: Like       this
It is 2009
It is 2009, 11/11/2009 11:41:51 AM to be more precise
It is 2009, Wednesday November 11 2009 11:41:51 to be even more precise
The value of pi is 3.141593
The value of pi to two decimal places is 3.14
They cost $99.0000 per 100
They cost $99.0000 per 1000
They cost $99.0000 per 10000
Logicals can be True or False
Logicals can also be Yes or No

Finding the Length of a Recital String

• strlen() - return the numeric length of a string

numeric = strlen(string as character)

Converting a String Into an Array

• astore() - fill an array from a string with separate character elements and return the number of elements

numeric = astore(arrayname, string as character, separator as character)

Converting an Array into a String

• astring() - return an array as a character string, with the elements separated by a comma or other specified character

character = astring(arrayname [, separator as character])

String Conversion Functions

• ctod() - perform character to date conversion

date = ctod(string as character)

• dtoc() - perform date to character conversion

character = dtoc(date as date)

• dtos() - perform date to string conversion

YYYYMMDD as character = dtos(date as date)

• etos() - perform expression to string conversion

character = etos(expression as expression)

• stod() - perform string to date conversion

date = stod(YYYYMMDD as character)

• val() - perform string to numeric conversion

numeric = val(string as character)

Removing Leading and Trailing Whitespace from a Recital String

• alltrim() - remove leading and trailing whitespace

character = alltrim(string as character)

• ltrim() - remove leading whitespace

character = ltrim(string as character)

• rtrim() - remove trailing whitespace

character = rtrim(string as character)

• trim() - remove trailing whitespace

character = trim(string as character)

Padding Recital Strings

• lpad() - remove leading whitespace

character = lpad(string as character)

• rpad() - remove trailing whitespace

character = rtrim(string as character)

• trim() - remove trailing whitespace

character = trim(string as character)

Comparing Strings in Recital

The inlist() function checks whether a character string exists in a specified list of strings.

logical = inlist(searchfor as character, liststring1 as character, liststring2 as character [,...])

The strcmp() and strcasecmp() functions are used to compare two strings, character by character. They differ in that strcmp() does a case-sensitive comparison and strcasecmp() a case-insensitive comparison.

numeric = strcmp(string1 as character, string2 as character)

numeric = strcasecmp(string1 as character, string2 as character)

String Comparison Functions Return Value

The strcmp() and strcasecmp() functions return a numeric value as follows:

Searching for and Replacing Characters and Substrings in a Recital String

• at() - search for a character or substring in a character string and return its starting position

numeric = at(searchforthis as character, inthis as character [, occurrence as numeric)

• occurs() - check how many times a character or substring appears in a character string

numeric = occurs(searchforthis as character, inthis as character)

• str_replace() - search for and replace text within a character string or memo field

character = str_replace(replacethis as character, withthis as character, inthis as character [, replaced as numeric])

• strtran() - search for and replace text within a character string or memo field

character = strtran(inthis as character, replacethis as character, withthis as character [, starthere as numeric [, repeat as numeric]])

• stuff() - replace text within a character string or memo field

character = stuff(inthis as character, starthere as numeric, characters as numeric, withthis as character)

Miscellaneous String Functions

Summary