Sources of errors
Human errors – GIGO and input errors
GIGO – Garbage in Garbage out
- If invalid data is entered in a computer program, the resulting output will also be
invalid
- Programmers must take measures to prevent GIGO errors
Arithmetic errors
Rounding
- When numbers are rounded, accuracy is lost on the decimal places after which
the rounding took place
Truncating
- Truncating a real number to an integer loses all decimal values
Fixed number of bits
- The number of bits available determines the highest and lowest numbers that
can be contained. If a number is outside of that range, it cannot be stored
Overflow
- Calculations that result in answers that exceed the max value for a data type
will still be performed but the answer will be incorrect
Data transmission errors
Common cable problems
Atmospheric conditions
- Moisture of heat can cause damage to the cable and make it unable to carry
data
Distance limits
- Cables can only carry signals over a limited distance, then attenuation (loss of
ability to continue carrying the signal) occurs
Interference-causing devices
- Magnetic or electrical interference
Programming errors
Bugs – catastrophic errors caused by programmers
description Cause
A rocket exploded seconds An overflow – an error in the conde that converted
after launch a 64-bit floating point number to a 16-bit signed
integer
An orbiter burned up in mars There was a confusion in calculations that
atmosphere involved English/metric unit conversions
Bugs in car systems A variety of errors in the embedded software of
smart cars
Solutions for errors
Verification
What is data verification
- a process of preventing errors when data is copied from one medium to
another, ensuring its completeness, correctness, and consistency
Validation
what is data validation
- A extensive number of checks applied to data
Human errors – GIGO and input errors
GIGO – Garbage in Garbage out
- If invalid data is entered in a computer program, the resulting output will also be
invalid
- Programmers must take measures to prevent GIGO errors
Arithmetic errors
Rounding
- When numbers are rounded, accuracy is lost on the decimal places after which
the rounding took place
Truncating
- Truncating a real number to an integer loses all decimal values
Fixed number of bits
- The number of bits available determines the highest and lowest numbers that
can be contained. If a number is outside of that range, it cannot be stored
Overflow
- Calculations that result in answers that exceed the max value for a data type
will still be performed but the answer will be incorrect
Data transmission errors
Common cable problems
Atmospheric conditions
- Moisture of heat can cause damage to the cable and make it unable to carry
data
Distance limits
- Cables can only carry signals over a limited distance, then attenuation (loss of
ability to continue carrying the signal) occurs
Interference-causing devices
- Magnetic or electrical interference
Programming errors
Bugs – catastrophic errors caused by programmers
description Cause
A rocket exploded seconds An overflow – an error in the conde that converted
after launch a 64-bit floating point number to a 16-bit signed
integer
An orbiter burned up in mars There was a confusion in calculations that
atmosphere involved English/metric unit conversions
Bugs in car systems A variety of errors in the embedded software of
smart cars
Solutions for errors
Verification
What is data verification
- a process of preventing errors when data is copied from one medium to
another, ensuring its completeness, correctness, and consistency
Validation
what is data validation
- A extensive number of checks applied to data
