# Is integration tiresome for you too?

1. Oct 24, 2013

### ainster31

Integration is so mindlessly tiring!

Finding the Fourier series of a function is so long and boring. I don't even get to use my brain to think. Just mindlessly integrating for several pages.

So mind-numbingly boring...

2. Oct 24, 2013

### arildno

Tip:
Do it with Bessel functions for a change!

3. Oct 24, 2013

### lisab

Staff Emeritus
hmm...now that I think about it, I didn't like integration much at all when I first learned it. I wanted to go back to that awesome differentiation.

That preference didn't last long though. Integration became just another cool tool in my toolbox.

4. Oct 24, 2013

### dipole

Theres a reason people compiled integral tables

5. Oct 24, 2013

### gravenewworld

I hate doing it. It's a waste of time if it isn't easy and can't be done in 5 minutes. That's why we have computers and tables. What's more important is the information that an integral spits out.

6. Oct 24, 2013

### MathematicalPhysicist

@gravenewworld, it's good you're not trying to be a mathematician or a theoretical physicist or a theoretical engineer. Most work isn't done in 5 minutes... :-D

7. Oct 25, 2013

### gravenewworld

Nah I'm not a theorist, I work in the real world. It's amazing how effective printing out a curve on a peice of paper, cutting it out, and weighing the paper on a scale again is for numerically calculating an integral. No fancy tricks, computer programs, of advanced numerical methods needed .

There are curves that have god awful equations. Sure there may be some fancy techniques to describe it as a series or soemthing else, but I dont want to spend a week trying to figure it out. I want to know the AUC and clearance rate of my drug now. Old school tricks can still work very well. I even know some people that have solved 3-D problems by cutting out contour plots and weighing paper.

Last edited: Oct 25, 2013
8. Oct 25, 2013

### arildno

It is hardly the daily work of any professional within these groups to do integrals by hand, computing one Fourier coefficient after the other.

9. Oct 25, 2013

### MathematicalPhysicist

Obviously if someone already calculated for you the integral and you believe his calculations to be valid then there is no wrong in using his results.

But if the reference is not trustworthy, buildings may tumble.

10. Oct 25, 2013

### Claude Bile

This is just precious. It sounds like something my dad would do (a smart person, but very technology-averse).

FTR, numerical integration is pretty quick (quicker than cutting out bits of paper), once you get over the initial learning curve. Plus you can integrate over lots of dimensions and in all sorts of fancy coordinate systems. Software like Matlab has lots of pre-loaded scripts for computing integrals, doing Fourier transforms and the like.

Also FTR, I have done plenty of integrals by hand - usually to check simple cases and make sure the script is working-as-intended, before letting the computer attack general problems.

Claude.

11. Oct 25, 2013

### jackmell

Hi,

I'm working on a beautiful contour integral:

The beautiful part of it is where the integration path is going: it's traversing, weaving is a better word, through a wonderfully beautiful object called a multi-valued function and if you saw a picture of it, I think you'd agree. But there's much more to it than that through the concept of "analytic continuation", that is, how we can analytically extend the definition of a function beyond the bounds of it's definition. Riemann used analytic continuation to extend the definition of the Euler product and in so doing, invented the zeta function and by association, created currently, the juiciest price in mathematics today: The Riemann hypothesis.

12. Oct 25, 2013

### WannabeNewton

What's an integral?

13. Oct 27, 2013

### meBigGuy

I think it is the part on the inside.

14. Oct 27, 2013

### AlephZero

Yup - don't confuse them with extegrals.

15. Oct 27, 2013

### lisab

Staff Emeritus

16. Oct 27, 2013

### SW VandeCarr

Back in the 70s when George Wallace was governor of Alabama (US), he opposed integration in the schools.

Last edited: Oct 27, 2013
17. Oct 27, 2013

### meBigGuy

That's what differentiated him (from humanity?)

18. Oct 27, 2013

### SW VandeCarr

Actually he was pro differentiation. He once said "Differentiation now, and differentiation forever!" or something like that. Anyway, he did not like integration. If you talked about integration around him, you'd be in a heap of trouble.

19. Oct 27, 2013

### lisab

Staff Emeritus
Sigh. Threads like this one always end up going off on tangents.

20. Oct 27, 2013

### meBigGuy

...... responsibly suppressing tangent jokes ......

I pretty much use the web to do my integrals, but I sure liked the construction paper idea. Luckily I never had a curve that would cause me to resort to such a tactic, but now it's in my toolbox.

21. Nov 2, 2013

### Superposed_Cat

use the rules like x^n ->x^n+1/n+1. if there is no antiderivative use wolfram oline or better yet download the app