IDL string 输出时显示小数点后位数

IDL> print, string(format='(f)', 100)

     100.0000000000000000

IDL> print, string(format='(f)', 100.0)

    100.0000000

IDL> print, string(format='(f)', 100.12345)

    100.1234512

IDL> print, string(format='(f)', 100.123456789)

    100.1234589

IDL> print, string(format='(f0.0)', 100.0)

100.000000

IDL> print, string(format='(f0.0)', 100)

100.000000

IDL> print, string(format='(f0.10)', 100.123456789)

100.1234588623

IDL> print, string(format='(f0.11)', 100.123456789d)

100.12345678900