Change the format of numbers

How-to 15 steps, run in order in one session. Every step was executed against the engine and the output below is what it produced.

Step 1

Output

Step 2

5 / 15

Output

1/3

Step 3

1234.

Output

1234.

Step 4

3 + 5I

Output

3 + 5*I

Step 5

2 / 3 + 5 / 7I

Output

2/3 + (5*I)/7

Step 6

1. + 5 / 7I

Output

1. + 0.7142857142857143*I

Step 7

N[Pi]

Output

3.141592653589793

Step 8

2.Pi

Output

6.283185307179586

Step 9

NumberForm[N[10Pi], 3]

Output

NumberForm[31.41592653589793, 3]

Step 10

NumberForm[N[Pi], {3, 10}]

Output

NumberForm[3.141592653589793, {3, 10}]

Step 11

AccountingForm[5.4]
AccountingForm[-5]
AccountingForm[10 ^ 12]

Output

AccountingForm[1000000000000]

Step 12

ScientificForm[1234567890000., 4]

Output

ScientificForm[1.23456789*^12, 4]

Step 13

EngineeringForm[N[E ^ 10], 5]

Output

EngineeringForm[22026.465794806703, 5]

Step 14

BaseForm[30, 2]

Output

BaseForm[30, 2]

Step 15

1 + NumberForm[2, 5]

Output

1 + NumberForm[2, 5]

Functions used