Why does my else doesnt work?

Please help. I'm learning how to use matlab on my own but I don't know why my if-else code won't work.

>> a = [-3.821; 0.135; 5.995; -5.557; -4.041; -3.094; -3.244; -3.074; -1.241; -4.216; -2.834; -0.424; 5.337; -0.088; 2.985; 4.136; 1.939; 6.031; -2.607; 3.340]

a =

-3.8210

0.1350

5.9950

-5.5570

-4.0410

-3.0940

-3.2440

-3.0740

-1.2410

-4.2160

-2.8340

-0.4240

5.3370

-0.0880

2.9850

4.1360

1.9390

6.0310

-2.6070

3.3400

>> b = [-1.529; -2.882; 1.287; 3.822; 0.422; -4.387; 3.107; -3.513; 4.760; -5.205; 2.265; -4.442; 6.247; -2.788; -2.688; -1.761; 1.987; 4.484; 0.052; -2.763]

b =

-1.5290

-2.8820

1.2870

3.8220

0.4220

-4.3870

3.1070

-3.5130

4.7600

-5.2050

2.2650

-4.4420

6.2470

-2.7880

-2.6880

-1.7610

1.9870

4.4840

0.0520

-2.7630

>> c = (a.^2 + b.^2).^(1/2)

c =

4.1156

2.8852

6.1316

6.7445

4.0630

5.3683

4.4919

4.6680

4.9191

6.6983

3.6279

4.4622

8.2164

2.7894

4.0169

4.4953

2.7763

7.5153

2.6075

4.3347

>> d = atand(a./b)

d =

68.1908

-2.6819

77.8837

-55.4805

-84.0382

35.1940

-46.2358

41.1871

-14.6125

39.0071

-51.3673

5.4525

40.5083

1.8079

-47.9969

-66.9370

44.2995

53.3695

-88.8573

-50.4009

if (d<0)

e= 360-d;

else

e==d

end

Answer 1

[David Hill]

 a = [-3.821; 0.135; 5.995; -5.557; -4.041; -3.094; -3.244; -3.074; -1.241; -4.216; -2.834; -0.424; 5.337; -0.088; 2.985; 4.136; 1.939; 6.031; -2.607; 3.340];
 b = [-1.529; -2.882; 1.287; 3.822; 0.422; -4.387; 3.107; -3.513; 4.760; -5.205; 2.265; -4.442; 6.247; -2.788; -2.688; -1.761; 1.987; 4.484; 0.052; -2.763];
 c = (a.^2 + b.^2).^(1/2);
 d = atand(a./b)

d = 20×1

68.1908 -2.6819 77.8837 -55.4805 -84.0382 35.1940 -46.2358 41.1871 -14.6125 39.0071

 e = d;
 e(d<0)=360-d(d<0)

e = 20×1

68.1908 362.6819 77.8837 415.4805 444.0382 35.1940 406.2358 41.1871 374.6125 39.0071

Answer 2

[Chandler Hall]

You can use conditional statements to modify a variable directly, known as logical indexing. Try:

d(d < 0) = 360 + d(d < 0)

See here or here for more examples.

Answer 3

[RAGHUNATHRAJU DASHARATHA]

As per my understanding you are using conditional statement if-else to get your output but unable to do it because in else condition you wrote e==d which does the element by element comparisons and returns an array with elements set to logical 1 (True) where the relation is true and elements set to logical 0(False) when the relation is false.

you can just replace it by e=d instead of e==d

a = [-3.821; 0.135; 5.995; -5.557; -4.041; -3.094; -3.244; -3.074; -1.241; -4.216; -2.834; -0.424; 5.337; -0.088; 2.985; 4.136; 1.939; 6.031; -2.607; 3.340];
 b = [-1.529; -2.882; 1.287; 3.822; 0.422; -4.387; 3.107; -3.513; 4.760; -5.205; 2.265; -4.442; 6.247; -2.788; -2.688; -1.761; 1.987; 4.484; 0.052; -2.763];
 c = (a.^2 + b.^2).^(1/2);
 d = atand(a./b)

d = 20×1

68.1908 -2.6819 77.8837 -55.4805 -84.0382 35.1940 -46.2358 41.1871 -14.6125 39.0071

if d<0
 e= 360-d;
else
    e=d
end

e = 20×1

68.1908 -2.6819 77.8837 -55.4805 -84.0382 35.1940 -46.2358 41.1871 -14.6125 39.0071

for further more refer the following link .