str$() -- convert a number into a string

 
a$=str$(a) 
b$=str$(x,"##.###") 
b$=str$(x,"###,###.##") 
b$=str$(x,"###,###.##","_.") 

The str$-function accepts a numeric argument and returns it as a string. This conversion between number and string can be controlled with the optional third argument (the format argument). See the following table of examples to learn about valid values of this argument. Note, that those examples fall in one of two categories: C-style and basic-style; the first 4 examples in the table below are C-style, the rest of the examples are basic-style. 

For more information on the C-style formats, you may refer to your favorite documentation on the C programming language. The basic-style formats are much simpler, they just depict the desired output, marking digits with '#'; groups of (usually three) digits may be separated with colons (','), the decimal dot must be marked by a literal dot ('.'). Moreover these characters (colons and dot) may be replaced by other characters to satisfy the needs of non-English (e.g. German) languages; see the examples below.

Note, that for clarity, each space in the result has been replaced by the letter 'x', because it would be hard to figure out, how many spaces are produced exactly otherwise.

Examples for the format argument


string |  Result for converting 1000*pi |      Description

%2.5f             3141.59265                      The '2' determines the minimum
                                                  length of the output; but if 
                                                  needed (as in the example) the 
                                                  output can be longer. 
                                                  The '5' is the number of digits 
                                                  after the decimal point.

%12.5f            xx3141.59265                    Two spaces (which appear as 'x') 
                                                  are added to pad the output to 
                                                  the requested length of 12 characters.

%012.5g           0000003141.6                    The 'g' requests, that the precision 
                                                  ('5') specifies the overall number of 
                                                  digits (before and after the decimal 
                                                  point).

%-12.5f           3141.59265xx                    The '-' requests the output to be 
                                                  left-centered (therefore the filling 
                                                  space appears at thi right).

 #####.##          x3141.59                        Each '#' specifies a digit 
                                                  (either before or after the dot), 
                                                  the '.' specifies the position of 
                                                  the dot. As 1000*pi does not 
                                                  have enough digits, the 5 requested 
                                                  digits before the dot are filled up 
                                                  with a space (which shows up as an 'x').

 ##,###.##         x3,141.59                       Nearly the same as above, but the colon
                                                  from the format shows up within the 
                                                  result.

 ##,###.## 
and an addtional 
argument of ".,"  x3.141,59                       Similar to the example above, but 
                                                  colon and dot are replaced with dot 
                                                  and colon respectivly.

 ##,###.## 
and an addtional 
argument of "_,"  x3_141,59                       Similar to the example above, but 
                                                  colon and dot are replaced with 
                                                  underscore and colon respectivly.

 #####             x3142                           The format string does not contain 
                                                  a dot, and therefore the result does 
                                                  not have any fractional digits.

 ##.###            ##.###                          As 1000*pi has 4 digits infront of 
                                                  the decimal dot and the format only 
                                                  specifies 2, yab does not know 
                                                  what to do; therefore it chooses just 
                                                  to reproduce the format string.

do 
	input "Please enter a format string: " f$ 
	a$=str$(1000*pi,f$) 
	for a=1 to len(a$) 
		if (mid$(a$,a,1)=" ") mid$(a$,a,1)="x" 
	next a 
	print a$ 
loop 

This is the program, that has been used to get the results shown in the table above.