Example 1: 
 
   > verbosity = 1;
 
   The verbosity level has been set to 1.
 
   > 0.1;
 
   Warning: Rounding occurred when converting the constant "0.1" to floating-point with 165 bits.
 
   If safe computation is needed, try to increase the precision.
 
   Warning: For at least 1 of the constants displayed in decimal, rounding has happened.
 
   0.1
 
   > showmessagenumbers = on;
 
   Displaying of message numbers has been activated.
 
   > 0.1;
 
   Warning (174): Rounding occurred when converting the constant "0.1" to floating-point with 165 bits.
 
   If safe computation is needed, try to increase the precision.
 
   Warning (478): For at least 1 of the constants displayed in decimal, rounding has happened.
 
   0.1
 
   > showmessagenumbers;
 
   on
 
   > showmessagenumbers = off!;
 
   > 0.1;
 
   Warning: Rounding occurred when converting the constant "0.1" to floating-point with 165 bits.
 
   If safe computation is needed, try to increase the precision.
 
   Warning: For at least 1 of the constants displayed in decimal, rounding has happened.
 
   0.1
 
 
 
Example 2: 
 
   > showmessagenumbers = on;
 
   Displaying of message numbers has been activated.
 
   > verbosity = 1;
 
   The verbosity level has been set to 1.
 
   > diff(0.1 * x + 1.5 * x^2);
 
   Warning (174): Rounding occurred when converting the constant "0.1" to floating-point with 165 bits.
 
   If safe computation is needed, try to increase the precision.
 
   Warning (478): For at least 1 of the constants displayed in decimal, rounding has happened.
 
   0.1 + x * 3
 
   > verbosity = 0;
 
   The verbosity level has been set to 0.
 
   > diff(0.1 * x + 1.5 * x^2);
 
   0.1 + x * 3
 
   > verbosity = 12;
 
   The verbosity level has been set to 12.
 
   > diff(0.1 * x + 1.5 * x^2);
 
   Warning (174): Rounding occurred when converting the constant "0.1" to floating-point with 165 bits.
 
   If safe computation is needed, try to increase the precision.
 
   Information (196): formally differentiating a function.
 
   Information (197): differentiating the expression '0.1 * x + 1.5 * x^2'
 
   Information (195): expression '0.1 + 2 * 1.5 * x' has been simplified to expression '0.1 + 3 * x'.
 
   Warning (478): For at least 3 of the constants previously displayed in decimal, rounding has happened.
 
   Warning (478): For at least 1 of the constants displayed in decimal, rounding has happened.
 
   0.1 + x * 3