Engineers: Do you use the notation log for natural log or log base 10.

[DVK916]

In all of my classes so far we have used it to mean natural log. And we write base 10 if it is log base 10. This is different than what was done in highschool, and I have been told engineers still use log to represent log base 10 and ln to be natural log, as was done in high school.

Just wondering, what notations engineers use.

 

[Heisenberg]

It wouldn't surprise me. Those wacky engineers use j for the square root of -1 too. Us physicists use the proper ln for natural log and i for sqrt(-1).

 

[BigJ]

In the intro classes I've taken so far (taking intro eng. courses, even though I'm a CS major) ln = the natural log.

 

[TuxDave]

I'm an engineer and I use the high school notation. Log = Log10 and Ln = Natural Log. But then again I usually write in the base anyways for anything other than Ln.

 

[TuxDave]

Originally posted by: Heisenberg
It wouldn't surprise me. Those wacky engineers use j for the square root of -1 too. Us physicists use the proper ln for natural log and i for sqrt(-1).

sin(wt)+j*cos(wt) ftw....

 

[hypn0tik]

Originally posted by: Heisenberg
It wouldn't surprise me. Those wacky engineers use j for the square root of -1 too. Us physicists use the proper ln for natural log and i for sqrt(-1).

They do it because i is usually reserved for current.

We use log at University but ln in highschool. It annoys me a bit as in math courses it refers to base e, but in electronics courses, it refers to base 10.

 

[SVT Cobra]

Originally posted by: hypn0tik

Originally posted by: Heisenberg
It wouldn't surprise me. Those wacky engineers use j for the square root of -1 too. Us physicists use the proper ln for natural log and i for sqrt(-1).

They do it because i is usually reserved for current.

We use log at University but ln in highschool. It annoys me a bit as in math courses it refers to base e, but in electronics courses, it refers to base 10.

LOL I have gotten confused about the same thing before for a second or two.

 

[hypn0tik]

Originally posted by: TuxDave

Originally posted by: Heisenberg
It wouldn't surprise me. Those wacky engineers use j for the square root of -1 too. Us physicists use the proper ln for natural log and i for sqrt(-1).

sin(wt)+j*cos(wt) ftw....

Lol

 

[Heisenberg]

Originally posted by: hypn0tik

Originally posted by: Heisenberg
It wouldn't surprise me. Those wacky engineers use j for the square root of -1 too. Us physicists use the proper ln for natural log and i for sqrt(-1).

They do it because i is usually reserved for current.

We use log at University but ln in highschool. It annoys me a bit as in math courses it refers to base e, but in electronics courses, it refers to base 10.

We use I for current too, but we've mastered the subtle art of capitalization.

 

[hypn0tik]

Originally posted by: Heisenberg

Originally posted by: hypn0tik

Originally posted by: Heisenberg
It wouldn't surprise me. Those wacky engineers use j for the square root of -1 too. Us physicists use the proper ln for natural log and i for sqrt(-1).

They do it because i is usually reserved for current.

We use log at University but ln in highschool. It annoys me a bit as in math courses it refers to base e, but in electronics courses, it refers to base 10.

We use I for current too, but we've mastered the subtle art of capitalization.

Ah, but capitalized values are used by us to refer to DC values while lower case for AC values. There is a difference between capitalized and lower case subscripts as well.

 

[TuxDave]

Originally posted by: hypn0tik

Originally posted by: Heisenberg

Originally posted by: hypn0tik

Originally posted by: Heisenberg
It wouldn't surprise me. Those wacky engineers use j for the square root of -1 too. Us physicists use the proper ln for natural log and i for sqrt(-1).

They do it because i is usually reserved for current.

We use log at University but ln in highschool. It annoys me a bit as in math courses it refers to base e, but in electronics courses, it refers to base 10.

We use I for current too, but we've mastered the subtle art of capitalization.

Ah, but capitalized values are used by us to refer to DC values while lower case for AC values. There is a difference between capitalized and lower case subscripts as well.

I like how we make a differentiation between VOUT, Vout and vout. I can't remember which one is DC, small signal and combined though... haha. Is there a vOUT? oh man...

 

[hypn0tik]

Originally posted by: TuxDave

Originally posted by: hypn0tik

Originally posted by: Heisenberg

Originally posted by: hypn0tik

Originally posted by: Heisenberg
It wouldn't surprise me. Those wacky engineers use j for the square root of -1 too. Us physicists use the proper ln for natural log and i for sqrt(-1).

They do it because i is usually reserved for current.

We use log at University but ln in highschool. It annoys me a bit as in math courses it refers to base e, but in electronics courses, it refers to base 10.

We use I for current too, but we've mastered the subtle art of capitalization.

Ah, but capitalized values are used by us to refer to DC values while lower case for AC values. There is a difference between capitalized and lower case subscripts as well.

I like how we make a differentiation between VOUT, Vout and vout. I can't remember which one is DC, small signal and combined though... haha.

Hahaha. Yeah. Small signal is all lowercase if I'm not mistaken.

Also, earlier in the thread, I couldn't tell whether you were joking about sin(wt) + jcos(wt) for e^(jwt).

 

[Heisenberg]

Originally posted by: hypn0tik

Originally posted by: Heisenberg

Originally posted by: hypn0tik

Originally posted by: Heisenberg
It wouldn't surprise me. Those wacky engineers use j for the square root of -1 too. Us physicists use the proper ln for natural log and i for sqrt(-1).

They do it because i is usually reserved for current.

We use log at University but ln in highschool. It annoys me a bit as in math courses it refers to base e, but in electronics courses, it refers to base 10.

We use I for current too, but we've mastered the subtle art of capitalization.

Ah, but capitalized values are used by us to refer to DC values while lower case for AC values. There is a difference between capitalized and lower case subscripts as well.

Ok, I can see that. We don't have any formal rules for capitalization like that, so you usually have to figure it out from context, which can really suck sometimes.

 

[hypn0tik]

Originally posted by: Heisenberg

Originally posted by: hypn0tik

Originally posted by: Heisenberg

Originally posted by: hypn0tik

Originally posted by: Heisenberg
It wouldn't surprise me. Those wacky engineers use j for the square root of -1 too. Us physicists use the proper ln for natural log and i for sqrt(-1).

They do it because i is usually reserved for current.

We use log at University but ln in highschool. It annoys me a bit as in math courses it refers to base e, but in electronics courses, it refers to base 10.

We use I for current too, but we've mastered the subtle art of capitalization.

Ah, but capitalized values are used by us to refer to DC values while lower case for AC values. There is a difference between capitalized and lower case subscripts as well.

Ok, I can see that. We don't have any formal rules for capitalization like that, so you usually have to figure it out from context, which can really suck sometimes.

Are we still wacky?

Edit: Nvm. don't answer that.

 

[lukatmyshu]

Actually (and i'd suspect that most CS people would agree with me) log(x) == log base 2 of X.

 

[DVK916]

Originally posted by: Heisenberg
It wouldn't surprise me. Those wacky engineers use j for the square root of -1 too. Us physicists use the proper ln for natural log and i for sqrt(-1).

Who is to say the proper term is ln for natural log.

In Mathematicians usually use log to refer to natural log.

 

[JayHu]

I use log to represent whatever base I'm working in.
I can usually figure it out. It's one of three choices: e, 10, 2. I can figure it out using the context. The markers can usually do so as well.

 

[KillerCharlie]

From my engineering experience, log is used for both base 10 and natural log. Mathematically they usually use ln for natural log but people still pronounce it as "log" since the base 10 version doesn't appear much in mathematics. In scientific programming (FORTRAN and I'm pretty sure C++), log is used for base e.

Usually it's pretty obvious what the base is and you can tell by the application.

 

[DVK916]

Originally posted by: JayHu
I use log to represent whatever base I'm working in.
I can usually figure it out. It's one of three choices: e, 10, 2. I can figure it out using the context. The markers can usually do so as well.

What usefullness does log base 10 have. Base e and 2 I understand, but how is 10 usefull.

 

[KillerCharlie]

Originally posted by: DVK916

Originally posted by: JayHu
I use log to represent whatever base I'm working in.
I can usually figure it out. It's one of three choices: e, 10, 2. I can figure it out using the context. The markers can usually do so as well.

What usefullness does log base 10 have. Base e and 2 I understand, but how is 10 usefull.

From my experience, it's purely for plotting. Some of the work I'm doing right now I'm plotting the error versus various parameters and plotting the log10 of the error collapses it down to a straight line.

 

[hypn0tik]

Originally posted by: DVK916

Originally posted by: JayHu
I use log to represent whatever base I'm working in.
I can usually figure it out. It's one of three choices: e, 10, 2. I can figure it out using the context. The markers can usually do so as well.

What usefullness does log base 10 have. Base e and 2 I understand, but how is 10 usefull.

Used extensively in EE for calculating gain and for making Bode plots.

Edit: Beat to it by KillerCharlie.

 

[iwantanewcomputer]

Originally posted by: hypn0tik

Originally posted by: DVK916

Originally posted by: JayHu
I use log to represent whatever base I'm working in.
I can usually figure it out. It's one of three choices: e, 10, 2. I can figure it out using the context. The markers can usually do so as well.

What usefullness does log base 10 have. Base e and 2 I understand, but how is 10 usefull.

Used extensively in EE for calculating gain and for making Bode plots.

Edit: Beat to it by KillerCharlie.

and reporting decibel levels. Using j for sqrt -1 is cause current is more important

I always use ln for natural log

 

[Oscar1613]

Originally posted by: Heisenberg
It wouldn't surprise me. Those wacky engineers use j for the square root of -1 too. Us physicists use the proper ln for natural log and i for sqrt(-1).

j is not the square root of -1. j is 1 with a phase shift of 90 degrees

 

[DVK916]

Originally posted by: hypn0tik

Originally posted by: DVK916

Originally posted by: JayHu
I use log to represent whatever base I'm working in.
I can usually figure it out. It's one of three choices: e, 10, 2. I can figure it out using the context. The markers can usually do so as well.

What usefullness does log base 10 have. Base e and 2 I understand, but how is 10 usefull.

Used extensively in EE for calculating gain and for making Bode plots.

Edit: Beat to it by KillerCharlie.

But is it used more than natural log.

I haven't ever seen any of my proffessors use log to be anything other than natural log. Strange how the same nation is used so differently in different fields of study.

 

[Eeezee]

Originally posted by: Heisenberg
It wouldn't surprise me. Those wacky engineers use j for the square root of -1 too. Us physicists use the proper ln for natural log and i for sqrt(-1).

QFT

In all of my courses ln = natural log, but it is just pronounced "log"