Engineers: how useful is linear algebra?

[alphatarget1]

im a 2nd year civil engineering student. i took calculus B last semester and passed with a B+. i thought i get to take a break from those 4 unit math classes and my advisor told me that if i were to go into structural engineering, it's better to take linear algebra than calculus C.

this is the 2nd week of classes and i'm struggling with linear algebra. I don't know why, i'm paying attention in class and doing all the homework but I JUST DONT GET IT. I'd take a calc class over this elementary linear algebra stuff any day of the week. i hated this stuff in high school and i still hate it. i'm thinking of dropping this class.

physics can be worked out... i thought physics was going to be my hardest class but i never thought that a math 3 unit class would put me down so much oh wait, it *is* an upper division class. i took a quiz on friday and i forgot to do the E21 thingys (where they have a diagonal of 1s and the row 1 column 2 position is changed i think?), the professor wrote "learn this or fail". but seriously, i just don't understand linear algebra. i'd be better off taking probability and statistics instead, since i at least have SOME background in it.

i used to think i could take any classes and not fail. if this keeps up i have a feeling im gonna fail my first college class

 

[CrazyDe1]

You'll probably use it in school but in the real world...no

 

[CanOWorms]

It depends on what field you're going to go in. I don't know anything about Civil Engineering though.

 

[Nocturnal]

I know a few people who have failed calc and then took it again and passed it.

 

[EmperorIQ]

dude, i'm feeling the same way you are, i want to drop my class!!!! but I"m going to face it one time or another so why not just stick with it? So far my professor always tells me that linear algebra is important because we might need it to calculate systems of circuits and such, like calculate current?? By far linear algebra has been the hardest math class for me. It just the concept of subspaces and such that seems hard to me. Give me enough time and i can spit out eigenvalues, RREF, GEM, and such, but i will never understand what these processes give me, and the significance of it =\

 

[Nocturnal]

Is linear algebra required for CS? Anyone know?

 

[alphatarget1]

Originally posted by: EmperorIQ
dude, i'm feeling the same way you are, i want to drop my class!!!! but I"m going to face it one time or another so why not just stick with it? So far my professor always tells me that linear algebra is important because we might need it to calculate systems of circuits and such, like calculate current?? By far linear algebra has been the hardest math class for me. It just the concept of subspaces and such that seems hard to me. Give me enough time and i can spit out eigenvalues, RREF, GEM, and such, but i will never understand what these processes give me, and the significance of it =\

the problem is this is the 2nd week of classes. i'm doing the most basic matrix multiplications and transformations. i think transportation engineering might be what im going into instead of structural.

 

[Hector13]

Originally posted by: CrazyDe1
You'll probably use it in school but in the real world...no

that completly depends on what you do for a living.. i use linear algebra every single day. Now, I may not need to put a matrix into row-echelon form by hand, but being familiar with such things can be crucial in many jobs.

 

[Hector13]

Originally posted by: Nocturnal
Is linear algebra required for CS? Anyone know?

in a good cs program, I sincerely hope so!

 

[Semidevil]

if you learn the very first things they teach you, it is usefull...........i.e, system of equations and solving for x's. But later, they teach you stuff about spaces, subspaces, vector spaces, R1, R2, R3, and R to the nth power.....that stuff is all theoritical and doesn't really have any usefull applications for engineers.........I think.....

 

[Pokey007]

Linear Algebra was the first real math class I've ever taken. It's no longer memorizing formulas and applying them, linear algebra is where math gets significantly harder but that much more beautiful.

 

[EmperorIQ]

Originally posted by: Semidevil
if you learn the very first things they teach you, it is usefull...........i.e, system of equations and solving for x's. But later, they teach you stuff about spaces, subspaces, vector spaces, R1, R2, R3, and R to the nth power.....that stuff is all theoritical and doesn't really have any usefull applications for engineers.........I think.....

see that's the thing, i'm perfectly fine when someone tells me to solve a system of equations, but when theories are popping all over the places i get confused, i'm sure it can be simplified in some way, but the professor that i'm taking is in love with math, especially linear algebra, so he tries to jump around and throw as much out as possible, trying to share the beauty of linear algebra, without considerations to whether or not a student can follow.

 

[EmperorIQ]

Originally posted by: Hector13

Originally posted by: Nocturnal
Is linear algebra required for CS? Anyone know?

in a good cs program, I sincerely hope so!

example of how linear algebra is useful for a program?

 

[QueHuong]

What are some examples of linear algebra (both simple and abstract)? I need to take LA1 and 2 and another math class to get a minor in math and I would like help deciding if I should go on with it.

 

[Armitage]

Linear algebra is very basic and is used almost everywhere that I've worked in. Some examples...

Structures: Most non-trivial problem, especially trusses will result in a system of linear equations. Finite Element Analysis (FEA) is nothing but an enourmous system of linear equations.
Aerodynamics: Computational Fluid Dynamics is similar to FEA ... big set of linear equations
Mechanics: One word: Tensors
Astrodynamics: Many/most coordinate transforms are given in terms of matrix equations. Understanding covariance is becoming critical to the field, and this is all matrices and eigensystems
Control theory: Again, many problems end up being a system of linear equations.

I recall solving certain kinds of circuits with matrices also in my required EE courses.

So it really is used everywhere ... understand it now, or suffer more later.

 

[Dissipate]

Originally posted by: Nocturnal
Is linear algebra required for CS? Anyone know?

It is where I am. I got As in all three of my calc classes but only a C in linear algebra. I hated that class.

 

[Armitage]

Originally posted by: Hector13

Originally posted by: CrazyDe1
You'll probably use it in school but in the real world...no

that completly depends on what you do for a living.. i use linear algebra every single day. Now, I may not need to put a matrix into row-echelon form by hand, but being familiar with such things can be crucial in many jobs.

Exactly ... the most used library in my personal code tool box is my set of linear algebra classes.

 

[Dissipate]

Originally posted by: EmperorIQ

Originally posted by: Hector13

Originally posted by: Nocturnal
Is linear algebra required for CS? Anyone know?

in a good cs program, I sincerely hope so!

example of how linear algebra is useful for a program?

One way of solving linear systems of equations is done using something called Kramer's Rule on computers. This is a linear algebra concept. I wrote a VB app that does this with up to 3 linear equations.

 

[Armitage]

Oh yea, how could I forget composites... how about inverting a 9x9 matrix where each element is a polynomial that takes about 1/8 to 1/4 page to write down! That's when you gain a true respect and adoration of Mathematica

 

[EmperorIQ]

but inverting a matrix takes up a lot of computation time. of O(n^3)?? so inverting wouldn't be useful, we should find ways around it, but using properties of linear algebra

 

[alphatarget1]

Originally posted by: ergeorge
Oh yea, how could I forget composites... how about inverting a 9x9 matrix where each element is a polynomial that takes about 1/8 to 1/4 page to write down! That's when you gain a true respect and adoration of Mathematica

NOOOOO
that's it, im switching my major to construction management
j/k. does anyone have any recommendation for like a book that helps me to understand linear algebra? my book sucks

 

[CrazyDe1]

Originally posted by: Hector13

Originally posted by: CrazyDe1
You'll probably use it in school but in the real world...no

that completly depends on what you do for a living.. i use linear algebra every single day. Now, I may not need to put a matrix into row-echelon form by hand, but being familiar with such things can be crucial in many jobs.

It might be in your line of work but in most ECE, EE, and CS jobs no one ever uses it. Also, keep in mind in the real world a lot of times you have no idea how to do something and you just figure it out as you go along.

 

[CrazyDe1]

repost

 

[Ionizer86]

Linear algebra is awesome! Solving multiple equations, finding a line through two points or a circle through 3. That's some pretty cool stuff that can be done very elegantly with [matrices]

 

[CanOWorms]

Originally posted by: CrazyDe1

Originally posted by: Hector13

Originally posted by: CrazyDe1
You'll probably use it in school but in the real world...no

that completly depends on what you do for a living.. i use linear algebra every single day. Now, I may not need to put a matrix into row-echelon form by hand, but being familiar with such things can be crucial in many jobs.

It might be in your line of work but in most ECE, EE, and CS jobs no one ever uses it. Also, keep in mind in the real world a lot of times you have no idea how to do something and you just figure it out as you go along.

Actually, computer vision and robotics use linear algebra pretty heavily.