I have tried sprintf("%.1e", x) but that gives me 6.3000e-16. How can I cut off the zeros and display just 6.3e-16? I am also displaying the numbers in a table.
EDIT: So now it is correctly display some numbers, but others aren't displayed in scientific notation at all. I am using R2018a.
Here is the code I am using
n = zeros(19,1);
a = zeros(19,1);
b = zeros(19,1);
c = zeros(19,1);
d = zeros(19,1);
format short
for i = 2:20
w = 1/(2000 * i);
x = 1/(1000 * i);
y = 1/(50 * i);
z = 1/(20 * i);
n(i-1) = sprintf("%d", i);
a(i-1) = sprintf("%.1e", w);
b(i-1) = sprintf("%.1e", x);
c(i-1) = sprintf("%.1e", y);
d(i-1) = sprintf("%.1e", z);
end
table( n, a, b, c, d )
and here is the output:
19×5 table
n a b c d
__ _______ _______ ______ ______
2 0.00025 0.0005 0.01 0.025
3 0.00017 0.00033 0.0067 0.017
4 0.00013 0.00025 0.005 0.013
5 0.0001 0.0002 0.004 0.01
6 8.3e-05 0.00017 0.0033 0.0083
7 7.1e-05 0.00014 0.0029 0.0071
8 6.3e-05 0.00013 0.0025 0.0063
9 5.6e-05 0.00011 0.0022 0.0056
10 5e-05 0.0001 0.002 0.005
11 4.5e-05 9.1e-05 0.0018 0.0045
12 4.2e-05 8.3e-05 0.0017 0.0042
13 3.8e-05 7.7e-05 0.0015 0.0038
14 3.6e-05 7.1e-05 0.0014 0.0036
15 3.3e-05 6.7e-05 0.0013 0.0033
16 3.1e-05 6.3e-05 0.0013 0.0031
17 2.9e-05 5.9e-05 0.0012 0.0029
18 2.8e-05 5.6e-05 0.0011 0.0028
19 2.6e-05 5.3e-05 0.0011 0.0026
20 2.5e-05 5e-05 0.001 0.0025
In your code, you are assigning a string to a double-float array. It looks like MATLAB automatically converts the string to a double to store it there. Thus, your formatting gets lost:
>> sprintf("%.1e", 1/1000)
ans =
"1.0e-03"
>> a=0;
>> a(1) = sprintf("%.1e", 1/1000)
a =
1.0000e-03
>> class(a)
ans =
'double'
Instead, use a string array:
a = strings(19,1);
%...
a(i-1) = sprintf("%.1e", w);
I'm not used to the new strings, and this behavior surprises me. Assigning a number to a string converts the number to a string, and assigning the string to a number converts it back to a number. This does not happen with the "old-fashioned" char arrays:
>> a=0;
>> a(1) = sprintf('%.1e', 1/1000);
Unable to perform assignment because the left and right sides have a different number of elements.
When using char arrays, store them in a cell array:
a = cell(19,1);
%...
a{i-1} = sprintf('%.1e', w);