Programming Forums > Application Development > C

oslan · Feb 8th, 2006, 7:18 AM

Dear friends,
I would like to get help from you guys on how to calculate the different between 2 input times (in minutes).

for example :

user_input_start_time = 10.25 /* means 10.25 AM */

user_input_end_time = 11.05 /* means 11.05 AM */

total_diff_time = user_input_end_time - user_input_start_time

from the above example , if use calculator, the answer is 0.80, but the
actual total_diff_time is only 0.40 (means 40 minutes).

How to calculate the above case in C programming.

Pls. help me.

Kind regards
Oslan

java_roshan · Feb 8th, 2006, 7:50 AM

Convert each time entity entered into a single unit of either seconds or minutes and display the answer in minutes/seconds....
i.e. for example if its 1:00 AM (say February 09th 2006) then, you have crossed 3600 seconds on that day...
if this is the first login ....

if it is 1:36 then it will be 3600 + 36 x 60 = 3600 + 2160 = 5760 seconds for the day
..
if this is the second login...

The difference in time....
5760 - 3600 = 2160 seconds
Divide by 60 will give u the minutes
2160 / 60 = 36 minutes

There might be certain functions in Borland C compiler to directly convert into a single unit for calcuation!
Hope you have understood...and this helps u out!

DaWei · Feb 8th, 2006, 8:02 AM

Quote:

user_input_start_time = 10.25 /* means 10.25 AM */

When converting your numbers, as mentioned by roshan, you don't want 10.25 to mean 10:25, as it means 10:15. I'm not saying that's what you're doing, just a tip.

java_roshan · Feb 8th, 2006, 8:12 AM

Quote:

Originally Posted by DaWei

When converting your numbers, as mentioned by roshan, you don't want 10.25 to mean 10:25, as it means 10:15. I'm not saying that's what you're doing, just a tip.

oslan...this would make your programming a bit simpler...I suppose!

jim mcnamara · Feb 8th, 2006, 5:07 PM

FWIW- you seem to assume the two times are from today, not 11:30pm and 1:27am tomorrow. You might want to check for that.

Otherwise, you'll have to use standard date routines - difftime, mktime, localtime.

oslan · Feb 8th, 2006, 9:07 PM

Dear friends,
Perhaps my earlier explaination was not so clear..
Let me explain again......

Example;

I want to calculate the Car Packing fee for certain period of time.
For this case, I need to key-in / input the following information;

1. Start_time (the time that the car owner park his/her car)
2. End_time (the time that the car owner leave the parking)

So, Duration_car_used_the_parking = End_time - Start_time;

once, I've the above duration then I can calculate the parking fee....

In my earlier message, I need help to show me on how to write the above calculation
in C programming.

I've tried to used difftime function but it doesn't work with the above manual input time.

FYI, I'm just start learning C programming and now I'm 'stuck' with my 1st. exercise.

Thanking you in advance for your kind help & advice.

Regards
oslan

nnxion · Feb 9th, 2006, 6:06 AM

Have a look at time.h.

DaWei · Feb 10th, 2006, 3:04 PM

Notice the difference between your use of "scanf" and spydoor's:

(Toggle Plain Text)

You:
scanf ("%d",&out_time);
He:
if(sscanf(out_time, "%d:%d", &out_time_hr, &out_time_min) != 2)

You are begging for runtime crashes and he is not. I leave it as an exercise for you to refer to the documentation and determine why. Meanwhile, please do not program any equipment on which people's lives depend.

spydoor · Feb 10th, 2006, 4:07 PM

Just don't pay attention to my math

Those 24s should be 60s to get seconds

Time limit on edits?

nnxion · Feb 10th, 2006, 5:00 PM

Quote:

Originally Posted by spydoor

Just don't pay attention to my math

Those 24s should be 60s to get seconds

Time limit on edits?

Yes time limits are there so people don't remove their content.
If you think it should change, say something about it here.

Feb 8th, 2006, 7:18 AM	#1
oslan Newbie Join Date: Feb 2006 Posts: 6 Rep Power: 0	need help on how to calculate between 2 input times. Dear friends, I would like to get help from you guys on how to calculate the different between 2 input times (in minutes). for example : user_input_start_time = 10.25 /* means 10.25 AM / user_input_end_time = 11.05 / means 11.05 AM / total_diff_time = user_input_end_time - user_input_start_time from the above example , if use calculator, the answer is 0.80, but the actual total_diff_time is only 0.40 (means 40 minutes). How to calculate the above case in C programming. Pls. help me. Kind regards Oslan Last edited by oslan; Feb 8th, 2006 at 7:19 AM. Reason: speeling error*

Feb 8th, 2006, 7:50 AM	#2
java_roshan Professional Programmer Join Date: Mar 2005 Location: Student of University of Mumbai, Maharashtra State, India Posts: 344 Rep Power: 5	Convert each time entity entered into a single unit of either seconds or minutes and display the answer in minutes/seconds.... i.e. for example if its 1:00 AM (say February 09th 2006) then, you have crossed 3600 seconds on that day... if this is the first login .... if it is 1:36 then it will be 3600 + 36 x 60 = 3600 + 2160 = 5760 seconds for the day .. if this is the second login... The difference in time.... 5760 - 3600 = 2160 seconds Divide by 60 will give u the minutes 2160 / 60 = 36 minutes There might be certain functions in Borland C compiler to directly convert into a single unit for calcuation! Hope you have understood...and this helps u out! __________________ Visit: http://www.somaiya.edu

Feb 9th, 2006, 6:06 AM	#7
nnxion Programming Guru Join Date: Jun 2005 Location: elemental plane Posts: 1,429 Rep Power: 6	Have a look at time.h. __________________ "Employ your time in improving yourself by other men's writings, so that you shall gain easily what others have labored hard for." -- Socrates

Feb 10th, 2006, 3:04 PM	#8
DaWei Resident Grouch Join Date: Jun 2005 Posts: 7,025 Rep Power: 12	Notice the difference between your use of "scanf" and spydoor's: (Toggle Plain Text) You: scanf ("%d",&out_time); He: if(sscanf(out_time, "%d:%d", &out_time_hr, &out_time_min) != 2) You: scanf ("%d",&out_time); He: if(sscanf(out_time, "%d:%d", &out_time_hr, &out_time_min) != 2) You are begging for runtime crashes and he is not. I leave it as an exercise for you to refer to the documentation and determine why. Meanwhile, please do not program any equipment on which people's lives depend. __________________ Abstraction doesn't make it impossible to write bad code; it makes it possible to write superior code. Contributor's Corner: Grumpy on C++ Exceptions DaWei on Pointers Politically Incorrect

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Feb 8th, 2006, 5:07 PM	#5
jim mcnamara Hobbyist Programmer Join Date: Jun 2005 Location: New Mexico Posts: 228 Rep Power: 5	FWIW- you seem to assume the two times are from today, not 11:30pm and 1:27am tomorrow. You might want to check for that. Otherwise, you'll have to use standard date routines - difftime, mktime, localtime.

Feb 8th, 2006, 9:07 PM	#6
oslan Newbie Join Date: Feb 2006 Posts: 6 Rep Power: 0	Dear friends, Perhaps my earlier explaination was not so clear.. Let me explain again...... Example; I want to calculate the Car Packing fee for certain period of time. For this case, I need to key-in / input the following information; 1. Start_time (the time that the car owner park his/her car) 2. End_time (the time that the car owner leave the parking) So, Duration_car_used_the_parking = End_time - Start_time; once, I've the above duration then I can calculate the parking fee.... In my earlier message, I need help to show me on how to write the above calculation in C programming. I've tried to used difftime function but it doesn't work with the above manual input time. FYI, I'm just start learning C programming and now I'm 'stuck' with my 1st. exercise. Thanking you in advance for your kind help & advice. Regards oslan

Feb 10th, 2006, 4:07 PM	#9
spydoor Programmer Join Date: Feb 2005 Posts: 64 Rep Power: 6	Just don't pay attention to my math Those 24s should be 60s to get seconds Time limit on edits?

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Programming Forums > Application Development > C

need help on how to calculate between 2 input times.