Skip to main content

Theory and Modern Applications

Table 2 Maximum absolute errors for q , u , and J at \(\pmb{M=20}\) and various choices of α and N for Example 5.1

From: A space-time spectral method for the time fractional diffusion optimal control problems

Errors

α

N  = 4

N  = 6

N  = 8

N  = 10

N  = 12

N  = 14

q

0.1

7.11E − 06

8.06E − 08

6.19E − 10

3.27E − 12

1.79E − 14

7.75E − 15

0.5

1.68E − 05

2.14E − 07

1.61E − 09

8.24E − 12

2.94E − 14

4.91E − 16

0.99

6.96E − 05

1.07E − 06

8.98E − 09

4.70E − 11

1.63E − 13

2.89E − 16

u

0.1

7.74E − 05

9.14E − 07

7.45E − 09

3.98E − 11

2.14E − 13

8.67E − 14

0.5

1.82E − 04

2.53E − 06

1.97E − 08

1.00E − 10

3.66E − 13

1.14E − 14

0.99

6.69E − 04

9.16E − 06

7.07E − 08

3.82E − 10

1.75E − 12

5.11E − 15

J

0.1

8.39E − 11

8.02E − 15

3.24E − 19

6.35E − 24

6.76E − 29

1.98E − 31

0.5

4.64E − 10

6.15E − 13

3.01E − 18

6.74E − 23

7.83E − 28

3.16E − 32

0.99

5.00E − 09

7.90E − 13

3.88E − 17

8.27E − 22

9.04E − 27

6.78E − 32