Unpredictable Under/Over Pct Results

[aeisman]

Describe the bug
It appears the under/over pct is still producing unexpected results. It works for the ratios of the example problem but when the ratios are changed, results are difficult to interpret.

To Reproduce
Steps to reproduce the behavior:
function calculate_smote_pct_under(; pct_over::Real = 0, minority_to_majority_ratio::Real = 0,)
if pct_over < 0
error("pct_over must be >=0")
end
if minority_to_majority_ratio <= 0
error("minority_to_majority_ratio must be >0")
end
result = 100minority_to_majority_ratio(100+pct_over)/pct_over
return result
end

Testing SMOTE

example 1 (works - ends up with 360 total in y2):

over_ratio = (180-20)/20 * 100
y = vcat(ones(20), zeros(180)); # 0 = majority, 1 = minority
X = hcat(rand(200, 10), y);
under_ratio = calculate_smote_pct_under(pct_over = over_ratio, minority_to_majority_ratio = 1.0)
x2, y2 = smote(X, y, k = 5, pct_under = under_ratio, pct_over = over_ratio)

example 2 (breaks - do not end up with 1226 in y2):

over_ratio = (613-268)/268 * 100
y = vcat(ones(268), zeros(613)); # 0 = majority, 1 = minority
X = hcat(rand(881, 10), y);
under_ratio = calculate_smote_pct_under(pct_over = over_ratio, minority_to_majority_ratio = 1.0)
x2, y2 = smote(X, y, k = 5, pct_under = under_ratio, pct_over = over_ratio)

Expected behavior
See above notes in #example 1 and #example 2