1073 scientific notation (20 分)
时间: 2023-06-05 18:47:46 浏览: 93
科学计数法是一种表示非常大或非常小的数字的方法,它将数字表示为一个基数和一个指数的乘积的形式。基数通常是一个小于10的数字,指数是一个整数,表示基数需要乘以10的几次方。例如,1.23 x 10^4表示为科学计数法时,基数为1.23,指数为4,表示1.23需要乘以10的4次方,即12300。科学计数法在科学、工程和数学等领域广泛应用。
相关问题
Q21: Which of the following is a valid user-defined output stream manipulator header? a. ostream& tab( ostream& output ) b. ostream tab( ostream output ) c. istream& tab( istream output ) d. void tab( ostream& output ) Q22: What will be output by the following statement? cout << showpoint << setprecision(4) << 11.0 << endl; a. 11 b. 11.0 c. 11.00 d. 11.000 Q23: Which of the following stream manipulators causes an outputted number’s sign to be left justified, its magnitude to be right justified and the center space to be filled with fill characters? a. left b. right c. internal d. showpos Q24: Which of the following statements restores the default fill character? a. cout.defaultFill(); b. cout.fill(); c. cout.fill( 0 ); d. cout.fill( ' ' ); Q25: When the showbase flag is set: a. The base of a number precedes it in brackets. b. Decimal numbers are not output any differently. c. "oct" or "hex" will be displayed in the output stream. d. Octal numbers can appear in one of two ways. Q26: What will be output by the following statements? double x = .0012345; cout << fixed << x << endl; cout << scientific << x << endl; a. 1.234500e-003 0.001235 b. 1.23450e-003 0.00123450 c. .001235 1.234500e-003 d. 0.00123450 1.23450e-003 Q27: Which of the following outputs does not guarantee that the uppercase flag has been set? a. All hexadecimal numbers appear in the form 0X87. b. All numbers written in scientific notation appear the form 6.45E+010. c. All text outputs appear in the form SAMPLE OUTPUT. d. All hexadecimal numbers appear in the form AF6. Q28: Which of the following is not true about bool values and how they're output with the output stream? a. The old style of representing true/false values used -1 to indicate false and 1 to indicate true. b. A bool value outputs as 0 or 1 by default. c. Stream manipulator boolalpha sets the output stream to display bool values as the strings "true" and "false". d. Both boolalpha and noboolalpha are “sticky” settings.
A21: a. ostream& tab( ostream& output ) is a valid user-defined output stream manipulator header.
A22: c. 11.00 will be output by the statement.
A23: c. internal is the stream manipulator that causes an outputted number’s sign to be left justified, its magnitude to be right justified and the center space to be filled with fill characters.
A24: d. cout.fill(' ') restores the default fill character, which is a space.
A25: c. "oct" or "hex" will be displayed in the output stream when the showbase flag is set.
A26: b. 1.23450e-003 and 1.23450e-003 will be output by the statements.
A27: d. All hexadecimal numbers appearing in the form AF6 does not guarantee that the uppercase flag has been set.
A28: a. The old style of representing true/false values used -1 to indicate false and 1 to indicate true is not true. False is represented by 0 and true is represented by any non-zero value.
plt.ticklabel_format
This is a method in the matplotlib library in Python that is used to format tick labels on a plot. It is used to change the way that numbers are displayed on the axis tick labels.
For example, the method `plt.ticklabel_format(style='sci', axis='y', scilimits=(0,0))` can be used to format the y-axis tick labels in scientific notation.
Here, `style` specifies the style of formatting (e.g. scientific notation), `axis` specifies the axis to be formatted (x, y or both), and `scilimits` specifies the range of exponents where scientific notation should be used.
There are several other options available in this method for formatting tick labels, including changing the precision of the numbers, adding a prefix or suffix, and using a different locale for number formatting.