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Trying to find the percentage of black pixels in an image (Python 2)
How do I find the location of my Python site-packages directory?Finding the index of an item given a list containing it in PythonPython try-elseFind all files in a directory with extension .txt in PythonHow to find if directory exists in PythonGrouping of lines in a text file and further processingPython read specific alternate linesLooping though file to extract linesRemove line character from a text file using Python (With a condition)What's the problem in this car counter problem?
.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty height:90px;width:728px;box-sizing:border-box;
Black pixels are represented by a B while non black pixels are represented by an N. For each image, calculate the percentage of black pixels to the nearest tenth.
I need the output as 80.0 % but I got 0.0, what's wrong with my code? Any advice would be appreciated! Thanks!
line1 = "BBBBBBBBBB"
line2 = "BBNNBBNNBB"
line3 = "BBNNBBNNBB"
line4 = "BBBBBBBBBB"
line5 = "BBBBNNBBBB"
line6 = "BBNBBBBNBB"
line7 = "BBBNNNNBBB"
line8 = "BBBBBBBBBB"
data = ["BBBBBBBBBB", "BBNNBBNNBB", "BBNNBBNNBB", "BBBBBBBBBB", "BBBBNNBBBB", "BBNBBBBNBB", "BBBNNNNBBB", "BBBBBBBBBB"]
def percentBlack(data):
numB = 0
numP = 0
for line in data:
for pixel in line:
if pixel == "B":
numB += 1
numP += 1
return round((numB/numP)*100,1)
print(percentBlack(data))
python python-2.7
edited Mar 9 at 3:46
Siong Thye Goh
1,72911016
asked Mar 9 at 3:15
JennyJenny
154
add a comment |
Black pixels are represented by a B while non black pixels are represented by an N. For each image, calculate the percentage of black pixels to the nearest tenth.
I need the output as 80.0 % but I got 0.0, what's wrong with my code? Any advice would be appreciated! Thanks!
line1 = "BBBBBBBBBB"
line2 = "BBNNBBNNBB"
line3 = "BBNNBBNNBB"
line4 = "BBBBBBBBBB"
line5 = "BBBBNNBBBB"
line6 = "BBNBBBBNBB"
line7 = "BBBNNNNBBB"
line8 = "BBBBBBBBBB"
data = ["BBBBBBBBBB", "BBNNBBNNBB", "BBNNBBNNBB", "BBBBBBBBBB", "BBBBNNBBBB", "BBNBBBBNBB", "BBBNNNNBBB", "BBBBBBBBBB"]
def percentBlack(data):
numB = 0
numP = 0
for line in data:
for pixel in line:
if pixel == "B":
numB += 1
numP += 1
return round((numB/numP)*100,1)
print(percentBlack(data))
python python-2.7
edited Mar 9 at 3:46
Siong Thye Goh
1,72911016
asked Mar 9 at 3:15
JennyJenny
154
1
Did you try to cast to floats/doubles before computing the % ? you might be doing an integer division: if the result is between [0, 1] then you might end up with 0 ! What does debug mode tell you about your variables ?
– LoneWanderer
Mar 9 at 3:25
add a comment |
Black pixels are represented by a B while non black pixels are represented by an N. For each image, calculate the percentage of black pixels to the nearest tenth.
I need the output as 80.0 % but I got 0.0, what's wrong with my code? Any advice would be appreciated! Thanks!
line1 = "BBBBBBBBBB"
line2 = "BBNNBBNNBB"
line3 = "BBNNBBNNBB"
line4 = "BBBBBBBBBB"
line5 = "BBBBNNBBBB"
line6 = "BBNBBBBNBB"
line7 = "BBBNNNNBBB"
line8 = "BBBBBBBBBB"
data = ["BBBBBBBBBB", "BBNNBBNNBB", "BBNNBBNNBB", "BBBBBBBBBB", "BBBBNNBBBB", "BBNBBBBNBB", "BBBNNNNBBB", "BBBBBBBBBB"]
def percentBlack(data):
numB = 0
numP = 0
for line in data:
for pixel in line:
if pixel == "B":
numB += 1
numP += 1
return round((numB/numP)*100,1)
print(percentBlack(data))
python python-2.7
edited Mar 9 at 3:46
Siong Thye Goh
1,72911016
asked Mar 9 at 3:15
JennyJenny
154
Black pixels are represented by a B while non black pixels are represented by an N. For each image, calculate the percentage of black pixels to the nearest tenth.
I need the output as 80.0 % but I got 0.0, what's wrong with my code? Any advice would be appreciated! Thanks!
line1 = "BBBBBBBBBB"
line2 = "BBNNBBNNBB"
line3 = "BBNNBBNNBB"
line4 = "BBBBBBBBBB"
line5 = "BBBBNNBBBB"
line6 = "BBNBBBBNBB"
line7 = "BBBNNNNBBB"
line8 = "BBBBBBBBBB"
data = ["BBBBBBBBBB", "BBNNBBNNBB", "BBNNBBNNBB", "BBBBBBBBBB", "BBBBNNBBBB", "BBNBBBBNBB", "BBBNNNNBBB", "BBBBBBBBBB"]
def percentBlack(data):
numB = 0
numP = 0
for line in data:
for pixel in line:
if pixel == "B":
numB += 1
numP += 1
return round((numB/numP)*100,1)
print(percentBlack(data))
python python-2.7
python python-2.7
edited Mar 9 at 3:46
Siong Thye Goh
1,72911016
asked Mar 9 at 3:15
JennyJenny
154
edited Mar 9 at 3:46
Siong Thye Goh
1,72911016
asked Mar 9 at 3:15
JennyJenny
154
edited Mar 9 at 3:46
Siong Thye Goh
1,72911016
edited Mar 9 at 3:46
Siong Thye Goh
1,72911016
edited Mar 9 at 3:46
Siong Thye Goh
1,72911016
1,72911016
asked Mar 9 at 3:15
JennyJenny
154
asked Mar 9 at 3:15
JennyJenny
154
asked Mar 9 at 3:15
JennyJenny
154
154
1
Did you try to cast to floats/doubles before computing the % ? you might be doing an integer division: if the result is between [0, 1] then you might end up with 0 ! What does debug mode tell you about your variables ?
– LoneWanderer
Mar 9 at 3:25
add a comment |
1
Did you try to cast to floats/doubles before computing the % ? you might be doing an integer division: if the result is between [0, 1] then you might end up with 0 ! What does debug mode tell you about your variables ?
– LoneWanderer
Mar 9 at 3:25
1
1
Did you try to cast to floats/doubles before computing the % ? you might be doing an integer division: if the result is between [0, 1] then you might end up with 0 ! What does debug mode tell you about your variables ?
– LoneWanderer
Mar 9 at 3:25
Did you try to cast to floats/doubles before computing the % ? you might be doing an integer division: if the result is between [0, 1] then you might end up with 0 ! What does debug mode tell you about your variables ?
– LoneWanderer
Mar 9 at 3:25
add a comment |
1 Answer
1
active
oldest
votes
Your code runs fine in Python 3.
I believe your code is written in Python 2 of which the division operator of two int produces an int. Here is a possible fix.
def percentBlack(data):
numB = 0
numP = 0
for line in data:
for pixel in line:
if pixel == "B":
numB += 1
numP += 1
return round((numB * 100.0/numP),1)
answered Mar 9 at 3:30
Siong Thye GohSiong Thye Goh
1,72911016
Yup I need it in Python 2. Great edit! That's what I need. So if I need a % symbol, do I just use this print statement: print(percentBlack(data)), "%"? Any other suggestion?
– Jenny
Mar 9 at 3:34
1
That should work, though I usually do print(str(percentBlack(data))+ "%")
– Siong Thye Goh
Mar 9 at 3:36
add a comment |
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1 Answer
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1 Answer
1
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active
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votes
Your code runs fine in Python 3.
I believe your code is written in Python 2 of which the division operator of two int produces an int. Here is a possible fix.
def percentBlack(data):
numB = 0
numP = 0
for line in data:
for pixel in line:
if pixel == "B":
numB += 1
numP += 1
return round((numB * 100.0/numP),1)
answered Mar 9 at 3:30
Siong Thye GohSiong Thye Goh
1,72911016
Yup I need it in Python 2. Great edit! That's what I need. So if I need a % symbol, do I just use this print statement: print(percentBlack(data)), "%"? Any other suggestion?
– Jenny
Mar 9 at 3:34
1
That should work, though I usually do print(str(percentBlack(data))+ "%")
– Siong Thye Goh
Mar 9 at 3:36
add a comment |
Your code runs fine in Python 3.
I believe your code is written in Python 2 of which the division operator of two int produces an int. Here is a possible fix.
def percentBlack(data):
numB = 0
numP = 0
for line in data:
for pixel in line:
if pixel == "B":
numB += 1
numP += 1
return round((numB * 100.0/numP),1)
answered Mar 9 at 3:30
Siong Thye GohSiong Thye Goh
1,72911016
Yup I need it in Python 2. Great edit! That's what I need. So if I need a % symbol, do I just use this print statement: print(percentBlack(data)), "%"? Any other suggestion?
– Jenny
Mar 9 at 3:34
1
That should work, though I usually do print(str(percentBlack(data))+ "%")
– Siong Thye Goh
Mar 9 at 3:36
add a comment |
Your code runs fine in Python 3.
I believe your code is written in Python 2 of which the division operator of two int produces an int. Here is a possible fix.
def percentBlack(data):
numB = 0
numP = 0
for line in data:
for pixel in line:
if pixel == "B":
numB += 1
numP += 1
return round((numB * 100.0/numP),1)
answered Mar 9 at 3:30
Siong Thye GohSiong Thye Goh
1,72911016
Your code runs fine in Python 3.
I believe your code is written in Python 2 of which the division operator of two int produces an int. Here is a possible fix.
def percentBlack(data):
numB = 0
numP = 0
for line in data:
for pixel in line:
if pixel == "B":
numB += 1
numP += 1
return round((numB * 100.0/numP),1)
answered Mar 9 at 3:30
Siong Thye GohSiong Thye Goh
1,72911016
answered Mar 9 at 3:30
Siong Thye GohSiong Thye Goh
1,72911016
answered Mar 9 at 3:30
Siong Thye GohSiong Thye Goh
1,72911016
answered Mar 9 at 3:30
Siong Thye GohSiong Thye Goh
1,72911016
1,72911016
Yup I need it in Python 2. Great edit! That's what I need. So if I need a % symbol, do I just use this print statement: print(percentBlack(data)), "%"? Any other suggestion?
– Jenny
Mar 9 at 3:34
1
That should work, though I usually do print(str(percentBlack(data))+ "%")
– Siong Thye Goh
Mar 9 at 3:36
add a comment |
Yup I need it in Python 2. Great edit! That's what I need. So if I need a % symbol, do I just use this print statement: print(percentBlack(data)), "%"? Any other suggestion?
– Jenny
Mar 9 at 3:34
1
That should work, though I usually do print(str(percentBlack(data))+ "%")
– Siong Thye Goh
Mar 9 at 3:36
Yup I need it in Python 2. Great edit! That's what I need. So if I need a % symbol, do I just use this print statement: print(percentBlack(data)), "%"? Any other suggestion?
– Jenny
Mar 9 at 3:34
Yup I need it in Python 2. Great edit! That's what I need. So if I need a % symbol, do I just use this print statement: print(percentBlack(data)), "%"? Any other suggestion?
– Jenny
Mar 9 at 3:34
1
1
That should work, though I usually do print(str(percentBlack(data))+ "%")
– Siong Thye Goh
Mar 9 at 3:36
That should work, though I usually do print(str(percentBlack(data))+ "%")
– Siong Thye Goh
Mar 9 at 3:36
add a comment |
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Did you try to cast to floats/doubles before computing the % ? you might be doing an integer division: if the result is between [0, 1] then you might end up with 0 ! What does debug mode tell you about your variables ?
– LoneWanderer
Mar 9 at 3:25