The Hexadecimal Number System and Memory Addressing
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Lab 7: Floating-Point Addition 0.0
Lab 7: Floating-Point Addition 0.0 Introduction In this lab, you will write a MIPS assembly language function that performs floating-point addition. You will then run your program using PCSpim (just as you did in Lab 6). For testing, you are provided a program that calls your function to compute the value of the mathematical constant e. For those with no assembly language experience, this will be a long lab, so plan your time accordingly. Background You should be familiar with the IEEE 754 Floating-Point Standard, which is described in Section 3.6 of your book. (Hopefully you have read that section carefully!) Here we will be dealing only with single precision floating- point values, which are formatted as follows (this is also described in the “Floating-Point Representation” subsec- tion of Section 3.6 in your book): Sign Exponent (8 bits) Significand (23 bits) 31 30 29 ... 24 23 22 21 ... 0 Remember that the exponent is biased by 127, which means that an exponent of zero is represented by 127 (01111111). The exponent is not encoded using 2s-complement. The significand is always positive, and the sign bit is kept separately. Note that the actual significand is 24 bits long; the first bit is always a 1 and thus does not need to be stored explicitly. This will be important to remember when you write your function! There are several details of IEEE 754 that you will not have to worry about in this lab. For example, the expo- nents 00000000 and 11111111 are reserved for special purposes that are described in your book (representing zero, denormalized numbers and NaNs). -
Generalized Linear Models (Glms)
San Jos´eState University Math 261A: Regression Theory & Methods Generalized Linear Models (GLMs) Dr. Guangliang Chen This lecture is based on the following textbook sections: • Chapter 13: 13.1 – 13.3 Outline of this presentation: • What is a GLM? • Logistic regression • Poisson regression Generalized Linear Models (GLMs) What is a GLM? In ordinary linear regression, we assume that the response is a linear function of the regressors plus Gaussian noise: 0 2 y = β0 + β1x1 + ··· + βkxk + ∼ N(x β, σ ) | {z } |{z} linear form x0β N(0,σ2) noise The model can be reformulate in terms of • distribution of the response: y | x ∼ N(µ, σ2), and • dependence of the mean on the predictors: µ = E(y | x) = x0β Dr. Guangliang Chen | Mathematics & Statistics, San Jos´e State University3/24 Generalized Linear Models (GLMs) beta=(1,2) 5 4 3 β0 + β1x b y 2 y 1 0 −1 0.0 0.2 0.4 0.6 0.8 1.0 x x Dr. Guangliang Chen | Mathematics & Statistics, San Jos´e State University4/24 Generalized Linear Models (GLMs) Generalized linear models (GLM) extend linear regression by allowing the response variable to have • a general distribution (with mean µ = E(y | x)) and • a mean that depends on the predictors through a link function g: That is, g(µ) = β0x or equivalently, µ = g−1(β0x) Dr. Guangliang Chen | Mathematics & Statistics, San Jos´e State University5/24 Generalized Linear Models (GLMs) In GLM, the response is typically assumed to have a distribution in the exponential family, which is a large class of probability distributions that have pdfs of the form f(x | θ) = a(x)b(θ) exp(c(θ) · T (x)), including • Normal - ordinary linear regression • Bernoulli - Logistic regression, modeling binary data • Binomial - Multinomial logistic regression, modeling general cate- gorical data • Poisson - Poisson regression, modeling count data • Exponential, Gamma - survival analysis Dr. -
13054-Duodecimal.Pdf
Universal Multiple-Octet Coded Character Set International Organization for Standardization Organisation Internationale de Normalisation Международная организация по стандартизации Doc Type: Working Group Document Title: Proposal to encode Duodecimal Digit Forms in the UCS Author: Karl Pentzlin Status: Individual Contribution Action: For consideration by JTC1/SC2/WG2 and UTC Date: 2013-03-30 1. Introduction The duodecimal system (also called dozenal) is a positional numbering system using 12 as its base, similar to the well-known decimal (base 10) and hexadecimal (base 16) systems. Thus, it needs 12 digits, instead of ten digits like the decimal system. It is used by teachers to explain the decimal system by comparing it to an alternative, by hobbyists (see e.g. fig. 1), and by propagators who claim it being superior to the decimal system (mostly because thirds can be expressed by a finite number of digits in a "duodecimal point" presentation). • Besides mathematical and hobbyist publications, the duodecimal system has appeared as subject in the press (see e.g. [Bellos 2012] in the English newspaper "The Guardian" from 2012-12-12, where the lack of types to represent these digits correctly is explicitly stated). Such examples emphasize the need of the encoding of the digit forms proposed here. While it is common practice to represent the extra six digits needed for the hexadecimal system by the uppercase Latin capital letters A,B.C,D,E,F, there is no such established convention regarding the duodecimal system. Some proponents use the Latin letters T and E as the first letters of the English names of "ten" and "eleven" (which obviously is directly perceivable only for English speakers). -
Vigesimal Numerals on Ifẹ̀ (Togo) and Ifẹ̀ (Nigeria) Dialects of Yorùbá
Vigesimal Numerals on Ifẹ̀ (Togo) and Ifẹ̀ (Nigeria) Dialects of Yorùbá Felix Abídèmí Fábùnmi (Ilé-Ifẹ̀) Abstract This study intends to bring Ifẹ̀ (Togo) into a linguistic limelight using the numeral systems. Numerals are a very important aspect of the day to day socio-economic and linguistic life of Ifẹ̀ (Togo) people. The traditional Ifẹ̀ (Togo) number system is vigesimal. In this study, forty- two different number words are listed for Yorùbá Ifẹ̀ (Nigeria) and Yorùbá Ifẹ̀ (Togo) and compared with Standard Yorùbá. We compared the Ifẹ̀ (Togo) number words and counting patterns with that of the Standard Yorùbá and Ifẹ̀ (Nigeria) and discovered that, by the nature of the components of these numbers, majority of the basic number words are either bisyllabic or trisyllabic, each syllable having the form VCV for the cardinals, and CVCV for the ordinals. There are irregularities in tonality; there are also alternations in the sequences of the vowel (oral and nasalized) and consonant sounds. This work finds out that Ifẹ̀ (Togo) has two counting patterns. In the first pattern, it uses addition solely to derive the number words but with a counting pattern where 'ten', 'twenty' and the added number units are taken as a whole. In the second counting pattern, subtraction is used to derive number words but this is applicable only to three numbers i. e. seventeen – /mɛ́ɛtadínóɡú/, eighteen – /méèʤìdínóɡu/ and nineteen – /mɔ̀kɔ̃dínoɡ́ u/. The Ifẹ̀ (Togo) dialect of Yorùbá mostly uses additive number positions. The dialect favours additive number positions more than the subtractive and the multiplicative positions. In other words, higher numbers are frequently used as bases for addition not as bases for multiplication in Ifẹ̀ (Togo). -
Zero Displacement Ternary Number System: the Most Economical Way of Representing Numbers
Revista de Ciências da Computação, Volume III, Ano III, 2008, nº3 Zero Displacement Ternary Number System: the most economical way of representing numbers Fernando Guilherme Silvano Lobo Pimentel , Bank of Portugal, Email: [email protected] Abstract This paper concerns the efficiency of number systems. Following the identification of the most economical conventional integer number system, from a solid criteria, an improvement to such system’s representation economy is proposed which combines the representation efficiency of positional number systems without 0 with the possibility of representing the number 0. A modification to base 3 without 0 makes it possible to obtain a new number system which, according to the identified optimization criteria, becomes the most economic among all integer ones. Key Words: Positional Number Systems, Efficiency, Zero Resumo Este artigo aborda a questão da eficiência de sistemas de números. Partindo da identificação da mais económica base inteira de números de acordo com um critério preestabelecido, propõe-se um melhoramento à economia de representação nessa mesma base através da combinação da eficiência de representação de sistemas de números posicionais sem o zero com a possibilidade de representar o número zero. Uma modificação à base 3 sem zero permite a obtenção de um novo sistema de números que, de acordo com o critério de optimização identificado, é o sistema de representação mais económico entre os sistemas de números inteiros. Palavras-Chave: Sistemas de Números Posicionais, Eficiência, Zero 1 Introduction Counting systems are an indispensable tool in Computing Science. For reasons that are both technological and user friendliness, the performance of information processing depends heavily on the adopted numbering system. -
Midterm-2020-Solution.Pdf
HONOR CODE Questions Sheet. A Lets C. [6 Points] 1. What type of address (heap,stack,static,code) does each value evaluate to Book1, Book1->name, Book1->author, &Book2? [4] 2. Will all of the print statements execute as expected? If NO, write print statement which will not execute as expected?[2] B. Mystery [8 Points] 3. When the above code executes, which line is modified? How many times? [2] 4. What is the value of register a6 at the end ? [2] 5. What is the value of register a4 at the end ? [2] 6. In one sentence what is this program calculating ? [2] C. C-to-RISC V Tree Search; Fill in the blanks below [12 points] D. RISCV - The MOD operation [8 points] 19. The data segment starts at address 0x10000000. What are the memory locations modified by this program and what are their values ? E Floating Point [8 points.] 20. What is the smallest nonzero positive value that can be represented? Write your answer as a numerical expression in the answer packet? [2] 21. Consider some positive normalized floating point number where p is represented as: What is the distance (i.e. the difference) between p and the next-largest number after p that can be represented? [2] 22. Now instead let p be a positive denormalized number described asp = 2y x 0.significand. What is the distance between p and the next largest number after p that can be represented? [2] 23. Sort the following minifloat numbers. [2] F. Numbers. [5] 24. What is the smallest number that this system can represent 6 digits (assume unsigned) ? [1] 25. -
2018-19 MAP 160 Byte File Layout Specifications
2018-19 MAP 160 Byte File Layout Specifications OVERVIEW: A) ISAC will provide an Eligibility Status File (ESF) record for each student to all schools listed as a college choice on the student’s Student Aid Report (SAR). The ESF records will be available daily as Record Type = 7. ESF records may be retrieved via the File Extraction option in MAP. B) Schools will transmit Payment Requests to ISAC via File Transfer Protocol (FTP) using the MAP 160byte layout and identify these with Record Type = 4. C) When payment requests are processed, ISAC will provide payment results to schools through the MAP system. The payment results records can be retrieved in the 160 byte format using the MAP Payment Results File Extraction Option. MAP results records have a Record Type = 5. The MAP Payment Results file contains some eligibility status data elements. Also, the same student record may appear on both the Payment Results and the Eligibility Status extract files. Schools may also use the Reports option in MAP to obtain payment results. D) To cancel Payment Requests, the school with the current Payment Results record on ISAC's Payment Database must transmit a matching record with MAP Payment Request Code = C, with the Requested Award Amount field equal to zero and the Enrollment Hours field equal to 0 along with other required data elements. These records must be transmitted to ISAC as Record Type = 4. E) Summary of Data Element Changes, revision (highlighted in grey) made to the 2018-19 layout. NONE 1 2018-19 MAP 160 Byte File Layout Specifications – 9/17 2018-19 MAP 160 Byte File Layout Specifications F) The following 160 byte record layout will be used for transmitting data between schools and ISAC. -
POINTER (IN C/C++) What Is a Pointer?
POINTER (IN C/C++) What is a pointer? Variable in a program is something with a name, the value of which can vary. The way the compiler and linker handles this is that it assigns a specific block of memory within the computer to hold the value of that variable. • The left side is the value in memory. • The right side is the address of that memory Dereferencing: • int bar = *foo_ptr; • *foo_ptr = 42; // set foo to 42 which is also effect bar = 42 • To dereference ted, go to memory address of 1776, the value contain in that is 25 which is what we need. Differences between & and * & is the reference operator and can be read as "address of“ * is the dereference operator and can be read as "value pointed by" A variable referenced with & can be dereferenced with *. • Andy = 25; • Ted = &andy; All expressions below are true: • andy == 25 // true • &andy == 1776 // true • ted == 1776 // true • *ted == 25 // true How to declare pointer? • Type + “*” + name of variable. • Example: int * number; • char * c; • • number or c is a variable is called a pointer variable How to use pointer? • int foo; • int *foo_ptr = &foo; • foo_ptr is declared as a pointer to int. We have initialized it to point to foo. • foo occupies some memory. Its location in memory is called its address. &foo is the address of foo Assignment and pointer: • int *foo_pr = 5; // wrong • int foo = 5; • int *foo_pr = &foo; // correct way Change the pointer to the next memory block: • int foo = 5; • int *foo_pr = &foo; • foo_pr ++; Pointer arithmetics • char *mychar; // sizeof 1 byte • short *myshort; // sizeof 2 bytes • long *mylong; // sizeof 4 byts • mychar++; // increase by 1 byte • myshort++; // increase by 2 bytes • mylong++; // increase by 4 bytes Increase pointer is different from increase the dereference • *P++; // unary operation: go to the address of the pointer then increase its address and return a value • (*P)++; // get the value from the address of p then increase the value by 1 Arrays: • int array[] = {45,46,47}; • we can call the first element in the array by saying: *array or array[0]. -
Bits and Bytes
BITS AND BYTES To understand how a computer works, you need to understand the BINARY SYSTEM. The binary system is a numbering system that uses only two digits—0 and 1. Although this may seem strange to humans, it fits the computer perfectly! A computer chip is made up of circuits. For each circuit, there are two possibilities: An electric current flows through the circuit (ON), or An electric current does not flow through the circuit (OFF) The number 1 represents an “on” circuit. The number 0 represents an “off” circuit. The two digits, 0 and 1, are called bits. The word bit comes from binary digit: Binary digit = bit Every time the computer “reads” an instruction, it translates that instruction into a series of bits (0’s and 1’s). In most computers every letter, number, and symbol is translated into eight bits, a combination of eight 0’s and 1’s. For example the letter A is translated into 01000001. The letter B is 01000010. Every single keystroke on the keyboard translates into a different combination of eight bits. A group of eight bits is called a byte. Therefore, a byte is a combination of eight 0’s and 1’s. Eight bits = 1 byte Capacity of computer memory, storage such as USB devices, DVD’s are measured in bytes. For example a Word file might be 35 KB while a picture taken by a digital camera might be 4.5 MG. Hard drives normally are measured in GB or TB: Kilobyte (KB) approximately 1,000 bytes MegaByte (MB) approximately 1,000,000 (million) bytes Gigabtye (GB) approximately 1,000,000,000 (billion) bytes Terabyte (TB) approximately 1,000,000,000,000 (trillion) bytes The binary code that computers use is called the ASCII (American Standard Code for Information Interchange) code. -
Subtyping Recursive Types
ACM Transactions on Programming Languages and Systems, 15(4), pp. 575-631, 1993. Subtyping Recursive Types Roberto M. Amadio1 Luca Cardelli CNRS-CRIN, Nancy DEC, Systems Research Center Abstract We investigate the interactions of subtyping and recursive types, in a simply typed λ-calculus. The two fundamental questions here are whether two (recursive) types are in the subtype relation, and whether a term has a type. To address the first question, we relate various definitions of type equivalence and subtyping that are induced by a model, an ordering on infinite trees, an algorithm, and a set of type rules. We show soundness and completeness between the rules, the algorithm, and the tree semantics. We also prove soundness and a restricted form of completeness for the model. To address the second question, we show that to every pair of types in the subtype relation we can associate a term whose denotation is the uniquely determined coercion map between the two types. Moreover, we derive an algorithm that, when given a term with implicit coercions, can infer its least type whenever possible. 1This author's work has been supported in part by Digital Equipment Corporation and in part by the Stanford-CNR Collaboration Project. Page 1 Contents 1. Introduction 1.1 Types 1.2 Subtypes 1.3 Equality of Recursive Types 1.4 Subtyping of Recursive Types 1.5 Algorithm outline 1.6 Formal development 2. A Simply Typed λ-calculus with Recursive Types 2.1 Types 2.2 Terms 2.3 Equations 3. Tree Ordering 3.1 Subtyping Non-recursive Types 3.2 Folding and Unfolding 3.3 Tree Expansion 3.4 Finite Approximations 4. -
Binary Bracelets
10010011011000110 10010011011000110110000100010001000001000 1001001101100011011000010001000111000110110 00010 001 1000001000 100 10011 011 000110 110000 10001000 001000 11000010 010000 010001010001000001000 100100110 010 010 110110000100010001000001000 1001001101 1000 110110000100010001000001000 1001001101 10001101100001000100010000 010 01000 10010011011000110110 00010 001 1000001000 100 10011 011 000110 110000 10001000001000 11000010 010000 01000 010 010 11000110110 00010 001 1000001000 100 10011 011 000110 110000 1000 10000 01 000 11000 010 010000 010 010 010 010 010 0100010010011011000110 10010011011000110110000100010001000001000 10010011011000110110000100010001110001101 10 00010 001BINARY 1000001000 101000110110000100010001000001000 BRACELETS 10010011011000110110 00010 001 1000001000 100 10011 011 000110 110000 10001000001000 11000010 010000 01000 11000110110 00010 001 1000001000 100 10011 011 000110 110000 1000 10000 01 000 1110 1100011011000010001000100000 000110 110000 10001000001000 11000010 010000 01000 11000110110 00010 001 1000001000 100 10011 011 000110 110000 1000 10010011011000110110 00010 001 1000001000 100 10011 011 Binary Code We are often used to representing numbers using ten digits: 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9. This is called a base-10, or decimal system. Binary code, however, uses only zeros and ones in a sequence of eight spots. We often to refer to these binary, or base-2, digits as “bits.” Binary code is used to communicate information between computers, communication devices, and many more modern technologies. It’s useful to build into electronic devices because it is a simple system that requires something turn on or off (where 1 is the on state and 0 is the off state). This activity will allow you to embed your own name or nickname in this secret code on a bracelet. The binary code for capital letters is found on the back of this page. -
2 1 2 = 30 60 and 1
Math 153 Spring 2010 R. Schultz SOLUTIONS TO EXERCISES FROM math153exercises01.pdf As usual, \Burton" refers to the Seventh Edition of the course text by Burton (the page numbers for the Sixth Edition may be off slightly). Problems from Burton, p. 28 3. The fraction 1=6 is equal to 10=60 and therefore the sexagesimal expression is 0;10. To find the expansion for 1=9 we need to solve 1=9 = x=60. By elementary algebra this means 2 9x = 60 or x = 6 3 . Thus 6 2 1 6 40 1 x = + = + 60 3 · 60 60 60 · 60 which yields the sexagsimal expression 0; 10; 40 for 1/9. Finding the expression for 1/5 just amounts to writing this as 12/60, so the form here is 0;12. 1 1 30 To find 1=24 we again write 1=24 = x=60 and solve for x to get x = 2 2 . Now 2 = 60 and therefore we can proceed as in the second example to conclude that the sexagesimal form for 1/24 is 0;2,30. 1 One proceeds similarly for 1/40, solving 1=40 = x=60 to get x = 1 2 . Much as in the preceding discussion this yields the form 0;1,30. Finally, the same method leads to the equation 5=12 = x=60, which implies that 5/12 has the sexagesimal form 0;25. 4. We shall only rewrite these in standard base 10 fractional notation. The answers are in the back of Burton. (a) The sexagesimal number 1,23,45 is equal to 1 3600 + 23 60 + 45.