3 ms·

What I liked is the awareness of the inexactness which is inherent in everything but which slide rules made more obvious. The joke from these times was "ask an

by acqq 6y ago

What I liked is the awareness of the inexactness which is inherent in everything but which slide rules made more obvious. The joke from these times was "ask an engineer what is 2 times 3 and he'll take out his slide rule and say between 5.9 and 6.1" Whoever thought that up maybe wanted to show how the engineers just use tools and don't think, but I've seen the opposite: it was some with just a theoretical mathematical training who blindly believed in every digit of the result they saw or produced, even when it was really meaningless or where it was obvious to me that the process resulted in an error.

segfaultbuserr 6y ago
The Art of Electronics warns the reader in the first chapter: > There is a tendency among beginners to want to compute resistor values and other circuit component values to many significant places, and the availability of inexpensive calculators has only made matters worse. There are two reasons you should try to avoid falling into this habit: (a) the components themselves are of finite precision (typical resistors are 5%; the parameters that characterize transistors, say, frequently are known only to a factor of two); (b) one mark of a good circuit design is insensitivity of the finished circuit to precise values of the components (there are exceptions, of course). You'll also learn circuit intuition more quickly if you get into the habit of doing approximate calculations in your head, rather than watching meaningless numbers pop up on a calculator display.
- jet_32951 6y ago
  There's a small book called "Errors of Observation and Their Treatment", ISBN 978-94-011-6928-8, which seemed dull in class but it emphasized being able to express and defend a numerical result as x +/- y . I did that thereafter and it made a lot of difference in my understanding of the result. It isn't done by many engineers any more, and I always look with suspicion on results claiming absurd precision. There isn't so much understanding there and people who engage in it are much more likely to submit work with multiple order-of-magnitude errors. They do not -know- the answer, they accept the line on the screen un-critically.
  - acqq 6y ago
    Those interested in this thread should also consider the posts by the user "anonytrary" while commenting this article in this context.

by acqq 6y ago

segfaultbuserr 6y ago

The Art of Electronics warns the reader in the first chapter: > There is a tendency among beginners to want to compute resistor values and other circuit component values to many significant places, and the availability of inexpensive calculators has only made matters worse. There are two reasons you should try to avoid falling into this habit: (a) the components themselves are of finite precision (typical resistors are 5%; the parameters that characterize transistors, say, frequently are known only to a factor of two); (b) one mark of a good circuit design is insensitivity of the finished circuit to precise values of the components (there are exceptions, of course). You'll also learn circuit intuition more quickly if you get into the habit of doing approximate calculations in your head, rather than watching meaningless numbers pop up on a calculator display.

jet_32951 6y ago
There's a small book called "Errors of Observation and Their Treatment", ISBN 978-94-011-6928-8, which seemed dull in class but it emphasized being able to express and defend a numerical result as x +/- y . I did that thereafter and it made a lot of difference in my understanding of the result. It isn't done by many engineers any more, and I always look with suspicion on results claiming absurd precision. There isn't so much understanding there and people who engage in it are much more likely to submit work with multiple order-of-magnitude errors. They do not -know- the answer, they accept the line on the screen un-critically.
- acqq 6y ago
  Those interested in this thread should also consider the posts by the user "anonytrary" while commenting this article in this context.