Difference: PrintingInAMPL (4 vs. 5)

Displaying Information

src="display.jpg"

Often when we display something (like variable values) many of the resulting numbers are 0 and we are only interested in the non-zero numbers. To stop any rows of zeros being displayed you can set the omit_zero_rows option:

src="omit.jpg"

You can also force display to use either tables or a single column by using the display_1col option. This option will use one column if the number of values to display is less than display_1col. The initial value of display_1col is 20, so any display command that shows less than 20 values will be displayed as a column. Setting display_1col to 0 forces display to use tables whenever possible.

src="display_1col.jpg"

Printing Information

By playing with the display options we can get the display command to format output in a nice way. However, we can also decide exactly what is displayed by using print and printf.

Printing to a File

All the output commands can be directed to a file. Adding > <filename&gt to the end of an output command creates the file with the given name and writes to it. Subsequent output commands append output to the file by adding >> <filename> to the commands. You should close your file when done so you can open it with another program. This is very useful for saving your solutions (in a useful format with printf), for example

• display.jpg:
  

• omit.jpg:
  

• display_1col.jpg:
  

• print.jpg:
  

• printf.jpg:
  

• printf_set.jpg:
  

• brewery.run: brewery.run